Chapter 20: Rapid Transit in Other Cities: London, Berlin, Budapest, Paris, Glasgow, Boston, Chicago, Philadelphia
Rapid Transit in New York City and in the Other Great Cities · Chamber of Commerce, 1906
London, A Railroad City. A London is a city of railways. In the city and its suburbs there are 531 stations. With the opening of roads now under construction, this number will be increased to more than 600. The length of all the lines-- trunk, local, and tubular-- exceeds 630 miles. There are 22 stations that may be regarded as termini. Into these each day go 4,252 suburban trains, and 445 other trains. The main object of rapid transit enterprises has been to get people from scattered termini to their places of business. Works, now nearing completion, will give 52 new stations, and new connections with existing underground railways. Electrification of the local lines, and separation as far as possible from trunk line traffic, will greatly increase the number of trains and greatly promote public convenience.
Mansion House Station-London Underground.
Four-fifths of the half-million people brought into central London before half-past ten every day are conveyed by railways; the remainder by tramways. The interior underground and surface roads carry not less than 600,000,000 passengers per annum. Of this number the District, Metropolitan, North London, City and South London, and Central London, carried 258,000,000 passengers in 1904. The Great Northern and City carried 14,000,000. The Great Northern, Piccadilly and Brompton will carry 116,000,000; the Charing Cross and Hampstead, 95,000,000; the Baker Street and Waterloo, 16,000,000; and the electrified District and Metropolitan, 100,000,000.
Broad Street Freight Station, London.
Roads Under Private Control. These roads are all private enterprises. The city derives no benefit from the privileges granted; and, beyond the restrictions embodied in the acts as to methods of construction and operation, the companies are free to pursue their own policies.
Map of London Underground Roads.
Thames Tunnel. The first tunnel built for use in the transportation of passengers was that under the Thames, from Wapping to Rotherhithe. The structure was designed by Isambard Brunel, father of the designer and builder of the Great Eastern, and it was there that the shield method was introduced, but not in connection with compressed air. Sir John Rennie, speaking of this work before the Institution of Civil Engineers in January, 1846, said that it was noted "for magnitude, boldness in design, and ingenuity in the means of construction, as well as for the extraordinary difficulties by which the work was attended."
Operations were commenced, in 1825, by a private company. The work was soon suspended. In 1837, a Treasury loan having been granted, it was taken up again. The following description is from the address referred to:
Description. "The two arched openings are 1,200 feet long, with spans 14 feet long and 16 feet 4 inches high. The openings are separated by a pier 4 feet thick, having 64 lateral arches of 4 feet span between the openings. The whole is surrounded with massive walls. The external walls, including openings, are 38 feet wide and 22 feet high. The structure is approached at each end by a perpendicular shaft 50 feet in diameter and 80 feet deep. The tunnel was intended to be carried forward to the surface of adjoining streets at such inclination that carriages could easily pass through it from both sides of the river. The crown of the tunnel is 16 feet below the bed of the river."
Method of Building. "In order to carry into effect this very difficult work unusual means and precautions were necessary. The ordinary wooden center framing scarcely presented sufficient strength and connection for that purpose. Brunel, accordingly, invented a cast-iron frame (which he termed a shield) sufficiently large to embrace the whole width and height of the intended structure, and divided into 36 compartments, each sufficiently large for a man to work in, yet capable of being closed to prevent access of water when required. The whole was impelled forward, as the work progressed, by powerful screws bearing against the completed walls behind. This ingenious contrivance was perfectly successful. Although the work was twice stopped by the irruption of the Thames, the apertures were closed with bags of clay and other materials, and the structure was continued with extraordinary perseverance until finally completed and opened to the public in 1843. The whole was constructed with bricks set in Roman cement, and cased inside with the same material; and it gives every prospect of permanence and solidity."
One of the claims brought forward in favor of this scheme was that the entrance on the street would not occupy more space than an omnibus. The tunnel now forms part of the line of the East London Railway.
Tower Subway. The first underground system, in the strict meaning of that term, was the Tower Subway, which was started in February, 1869, and finished in the following December. It was designed by Peter Barlow, and finished by his son. It was intended to provide means of communication, by omnibus, under the Thames and other large rivers. It was advertised as "the only system capable of relieving the street traffic of the Metropolis."
The following information in relation to this tunnel is condensed from an address by Charles B. Vignoles, president of the Institution of Civil Engineers, in January, 1870:
The subway consists of two shafts, one on Tower Hill, and the other on the opposite side of the river, near Tooley street, in the Borough. Each shaft is 10 feet inside diameter and is sunk about 60 feet, penetrating well inside the London clay. They are connected by a circular tube 7 feet clear diameter and 1,350 feet in length. The grade at each end is 1 in 40. Passengers are conveyed up and down in lifts operated by steam. Transit through the tunnel is made by omnibus along a single line of railway, the hauling being done by wire ropes. The shield was forced forward by screws, as in the former case, the tunnel being lined with cast-iron plates as the work progressed. The shield overlapped the finished tube "like the covering to the object glass of a large telescope." The length under the Thames was finished in 15 weeks, the cost being $90,000. Mr. Vignoles says: "In this way between 3,000 and 4,000 persons can be conveyed between Tower Hill and Tooley street daily at a charge of one penny only."
Both of these schemes were strictly local in character, and were intended to provide convenient means for passing the river, and to relieve congestion in the immediate neighborhood of their termini. They were not meant to form an integral part of any comprehensive plan of rapid transit. That they were afterward so used was due solely to circumstances of location.
Two Types of Underground Roads. From a paper by Basil Mott and David Hay, read before the International Engineering Congress at St. Louis last year, we find that the existing underground railways of London are of two distinct types, namely, those constructed just below the surface, and approached by stairs from the street level, and the deep level, or tube railways, built in the London clay, at depths varying from 40 to 100 feet, and approached by elevators.
Roads Opened. Fifty years ago an act of Parliament was obtained for the "North Metropolitan Railway, from Paddington to the Post Office, with extensions to Paddington and the Great Western Railway, to the General Post Office, to the London and North-Western Railway, and to the Great Northern Railway." Subsequently authority for further extensions was obtained, and the various parts of the road, which now constitute the inner circle of the underground system, were opened for traffic as follows:
|Paddington to Farringdon street (Metropolitan Railway)||1963|
|Farringdon street to Moorgate street (Metropolitan Railway)||1865|
|Paddington to South Kensington (Metropolitan Railway)||1868|
|South Kensington to Westminster (Metropolitan District)||1868|
|Westminster to Mansion House (Metropolitan District)||1868|
|Mansion House to Aldgate (Joint Line)||1876|
|Aldgate to Moorhead street (Metropolitan)||1884|
Other extensions, which are only partly underground, have been constructed as follows:
|Hammersmith and Paddington||1863|
|Baker Street and Swiss Cottage||1868|
|East London Railway, New Cross to Wapping (through Brunel's old Thames Tunnel)||1869|
|Wapping to Whitechapel, Great Eastern Railway||1876|
|Hammersmith and Ealing||1879|
|Connection with District Railway||1884|
|Earl's Court to Putney Bridge||1880|
|Putney Bridge to Wimbledon||1889|
|Whitechapel and Bow||1902|
|Ealing and South Harrow||1903|
Clay-Level Tunnels. Messrs. Mott and Hay say: "The enormous cost of constructing the shallow railways through the busy centers of London is, under existing circumstances, prohibitive; and, with the exception of the Whitechapel and Bow, no such railway has been carried out since the completion of the Circle from Aldgate to Moorhead street, in 1884. In order to avoid the heavy capital expenditure, the late J. H. Greathead proposed the alternative system of deep-level, iron-lined, tube railways constructed in the London clay, which is a strong impervious clay, and extends practically under the whole Metropolitan area."
Deep Level Lines. At the present time the existing deep lines and those under construction or authorized are as follows:
|City and South London||Opened 1890|
|Waterloo and City||Opened 1898|
|Central London||Opened 1900|
|Great Northern and City||Opened 1904|
|Baker Street and Waterloo||Under construction|
|Great Northern, Piccadilly and Brompton||Under construction|
|Charing Cross, Euston and Hampstead||Under construction|
|North West London||Authorized|
All of the deep tunnels are iron-lined tubes, circular in section, constructed under the streets to avoid the purchase of property, and at a sufficient depth to prevent interference with pipes and sewers.
Stations. "The station tunnels, containing the platforms, are generally 21 feet 2-1/2 inches internal diameter and from 300 to 400 feet in length, lined with concrete and tiled. The only property purchased is for the surface stations and the power station. Upon the station sites are sunk the shafts for lifts and stairs communicating with the platforms. The lifts are an essential feature of the deep-level tubes, and though adding to the cost of working the line, they enable the tunnels to be constructed in the clay, and have been generally adopted. These lifts are utilized during construction as working shafts from which all the tunnels are driven, and no openings are required in the streets. Consequently there is no disturbance of traffic."
Separate tunnels, having an average diameter of 11-1/2 feet, are provided for the up and down lines. The advantages of separate tunnels are presented in the following:
Description of Tunnels. "In narrow streets, where double-line tunnels would be impossible without encroaching upon adjoining property, the two tubes can be placed one over the other without difficulty, and no property need be purchased."
"The ventilation is assisted materially by the trains moving always in the same direction in each tunnel."
"The gradients, approaching and departing from the stations, can be arranged to give a steep gradient with the load when departing. These gradients, where feasible in practice, are made 1 to 30, with a fall of 10 feet, which secures a very rapid acceleration, and reduces the power required approximately 25 per cent. The approaching gradients are usually from 1 in 60 to 1 in 100. With both lines in one tunnel the gradients, with and against the load, are necessarily the same."
"Where headway is important in passing under existing railways, or deeplevel sewers, etc., two tunnels have an advantage. Two small single-line tunnels are cheaper than one large double-line one."
First Tube Railway. The pioneer of all tube railways was the City and South London, opened for traffic in 1890. The following paragraph is from a report to the Board of Rapid Transit Railroad Commissioners of New York, by William Barclay Parsons, chief engineer, in 1894:
Description of Tubes. "This line is interesting for two reasons: First, it was built by a totally different method of construction from the other London railways; second, it uses electricity for its motive power. It consists of two cast-iron tubular tunnels. These tubes are at a distance of from 40 to 80 feet beneath the surface, following generally the lines of the streets, and nearly always on the same level and distant a few feet from each other. In one street, however, which was so narrow as to prevent the tubes from being driven side by side without encroaching upon private property, one tube was depressed and carried beneath the other. According to the company's report the road has cost £267,000 per mile."
"The road is operated from 6 A.M. to 11:30 P.M., with a headway in the busy portion of the day of about 4 minutes. The longest distance between any two stations is three-quarters of a mile, and the shortest slightly less than half a mile. The street level at the stations is generally about 50 feet above the platform level, communication being maintained by means of two staircases and two elevators. The elevators cost annually about £2,650 to operate; a cost per passenger of about 1/10 penny or over 5 per cent. of the gross receipts. The fare is 2 pence for any distance."
Ventilation. "Ventilation is secured automatically by the piston action of the trains, which nearly fill the tunnel, so that each train propels in front of it a column of air which finds its way to the street through the stairways or elevator shafts, while the same train is sucking down through the previous station a similar amount of fresh air."
Growth. The following table is of value as showing the growth in the passenger traffic of this road:
|June, 1891||June, 1904|
|Length of line||3 miles, 12 chains||6 miles, 9 chains|
|Working expenses||£15,521 =79%||£36,569 = 45.58 %|
|Number of passengers carried||2,412,343||10,225,987|
|Dividend||Nil||2-1/2 per annum|
|Number of carriages||30||142|
|Number of locomotives||14||52|
Central London Line. The best known of the deep subways is the Central London. This is located under some of the most important sections of the city, as it extends from Shepherd's Bush to the Bank, a distance of about 6 miles. The first act authorizing the construction of this railway was passed in 1891; work was begun in 1894, and the line was opened in 1900.
Motive Power. At first the trains were drawn by electric locomotives, each train consisting of seven cars, giving a seating capacity of 48 passengers each, and drawn by a locomotive weighing 42 tons, the total weight of the train being 140 tons. It was found that the heavy locomotive caused vibrations in the tunnels, which were communicated to the surface and gave rise to complaints. It was, therefore, decided to adopt the system of multi-polar control, by which, from one point in the train, different cars could be actuated.
The maximum service of a train every two minutes is maintained during the two busy morning and evening hours. The operation for the first six months of last year was:
|Passengers per train mile||35.15|
These figures show that the average number of passengers carried per train on each trip is 203. The seating capacity of each train is 330.
Ventilation. Particular attention has been paid to the ventilation of this tunnel. At the Shepherd's Bush end a large fan is operated which draws the air through the whole tube every night. This fan is sufficiently powerful to clear the air twice during the three hours while the traffic is stopped. Chemical examination of the air in the tube showed that it was by no means bad, while bacteriological observations gave results that were better than in the street.
Northern City Line. The next important line to be opened was the Great Northern and City, in 1904. This runs from Finsbury Park to a station at the junction of Moorgate street, Princess street, and Lothbury. This tube connects with all the others by means of passageways. It is one of the most popular of all the tubes because of its extra diameter, its comfortable carriages, and its excellent ventilation.
Blackwall Tunnel. Thirty years ago it was recognized that additional river crossings were needed below London Bridge, but it was not until 1887 that the Blackwall Tunnel Act was obtained. The first proposition was to build three tunnels, two for vehicular traffic and one for foot passengers. This plan was afterward changed, and it was decided to build one tunnel large enough to accommodate traffic of every description. During the latter part of 1891 the contract was let to S Pearson & Son (who are now building the East River section of the Pennsylvania Railroad tunnels, New York,) for $4,215,640. Work was commenced the following year.
Plan. The total length of this tunnel is 6,200 feet, of which 1,200 feet are below the river. The central section, for a distance of 3,112 feet, is lined with cast iron. It is circular in section, with a clear diameter of 24 feet 3 inches, the roadway being 16 feet wide and the footpaths 3 feet 1-1/2 inches. It has no connection with any of the underground roads.
In a lecture before the Society of Arts in January of the present year Robert P. Porter discussed the question, "Will the ever-increasing traffic of London at once absorb all this new accommodation?" He answers as follows:
Earnings. "The American metropolis, with a capacity for carrying 1,200,000,000 passengers per annum, is preparing to carry 2,000,000,000 passengers; but experts in that city believe that in less than ten years from the completion of the present facilities the requirements will be 3,000,000,000. In both cities what may be called the traveling habit increases with the increase of convenience in transit. The number of journeys, per head of population, has increased in a generation, in London, from 23 to 200 journeys, and, in New York, from 47 to over 400. Based on the earnings of the Central London on a passenger traffic of 55,000,000, the Baker Street and Waterloo should earn £230,000. The Great Northern, Piccadilly and Brompton, with a passenger traffic of 85,000,000, should earn £358,000, while the earnings of the Charing Cross, Euston and Hampstead line, with its 75,000,000 passengers per annum, should be in the neighborhood of £316,000. With a common power house the working expenses should be less than 50 per cent. of the earnings, the Central London being just over 49 per cent. With the growth of London the roads will undoubtedly become profitable investments."
Cross-over Tunnel, London.
Ringbahn/Stadtbahn. The Ringbahn, or Circle Railway, was opened in 1877. The route was laid out with little or no regard for public convenience, and, like other similar circular railways, it did not meet the needs of the people concerned. The Stadtbahn, an elevated road built wherever possible on masonry and earthwork, and employing iron for street and river crossings, was opened in 1882. It was constructed on a purchased right of way; and as the undertaking was found to be too expensive for private capital, the German Government completed the work, mainly as a military expedient to facilitate the movement of troops. The total length is 74 miles. There are 5 miles of masonry arches, one mile of earth embankment, and one mile of iron structure. The route is through one of the best and most populous portions of Berlin. Much attention was given to architectural features. There are four tracks, two for local trains and two for trains from a distance. Of the 10 stations, those at the terminals and three others are for through trains, and at these baggage is received. The roofs of all the stations are made of iron and glass. The largest station is the Friedrich Strasse, having a length of 508 feet and a clear width of 125 feet. Statistics show that while the Ringbahn, with a much longer mileage, carried, in 1900, 37,000,000 passengers, the Stadtbahn carried 60,500,000.
Views of Berlin U-Bahn. (1) Below Strasse Viaduct; (2) Elevated Road Through Building; (3) Station at Schlessisches Tor; (4) Bridge and Station at Stralauer Tor.
Electric Road. Another line, called the Berlin Electric Elevated and Underground Railway, was commenced in 1897, and opened in 1902. It extends through the central part of the city from east to west. The underground part begins at the Zoological Garden, passes around Kaiser Wilhelm Gedachtniss-Kirche, and underneath the streets Tanuezien and Kleist to Nollendorf-Platz. Here the line rises to the surface. From this point it continues as an elevated structure through Oberaumstrasse, Skalitzecstrasse, Kottbuser Thor, and along Gitschinerstrasse, Hallesches Thor, and the Hallesches Ufer. It then crosses the Spree River by the Oberbaum Brucke, and runs through Straulauer Thor and Warschauer Platz to Warschauer Brucke.
Map of Berlin U-Bahn Routes.
Route. The total length of the underground and elevated lines is less than a dozen miles, the distance from the Warsaw Bridge to the Zoological Garden being about 7 miles. From the first station at Warschauer Bridge to Stralauer Gate is 351 yards, while from the latter to the next stop at Schlesisches Gate the distance is 495 yards. The next five overhead stations are at Oranien street, Kottbuser street, Prinzen street, Hallesches Gate and Mockern Bridge. These stops are from 606 to 1,120 yards apart, and the distance from Mockern Bridge to Buelow street is 1,665 yards. The stone arches of the overhead portion of the line comprise I,026 yards, while the steel viaducts and bridges cover a distance of 7,960 yards. One of the conditions of the grant was that the overhead viaducts should have a clear headroom of 15 feet above the road level at all street crossings. The platforms are on the same level as the car floors. They are about 250 feet long, and are covered for more than half their length. There are no waiting rooms, the elevated portion of the station consisting merely of a hall, staircases, and ticket-distributing devices. The elevated structure has two tracks of standard gauge, placed 3 meters apart. The smallest curves have a radius of about 80 meters.
Incline at Nollendorf Platz-Berlin.
Structural Features. The tunnels were constructed under streets, the top of the arch being 2 feet below the surface. The distance between the transverse girders is 5 feet, the rise of the arches 8 inches, and the total width of the subway 21 feet 3 inches. Dryness is insured by the use of asphalt sheathing in the trenches, side walls, and roofs. The center of the span is supported by a row of steel columns. The tunnel has niches in the walls at every 75 feet, and is drained by a culvert in the center of each track, which leads to a sump from which the water is pumped into the sewers. The inclines from the tunnels to the viaducts have grades of 1.38. This portion of the system starts at the west of the city, north of Charlottenburg, near the Zoological Garden, and terminates at Nollendorf Place. The total length of tunnel is 1,856 yards, and the tunnel approaches are 622 yards long.
Electrical Equipment. The power house is near the center of the line, where the road meets the Ringbahn at the Potsdam station. The third rail system of distribution is used. The trains weigh 80 tons loaded, and consist of three cars, the first and last being motor cars. They are provided with motors upon each of the four axles. The motors are geared to obtain a train speed of 30 kilometers per hour. Each train is made up of two third-class and one first-class car. The train headway is from 3 to 5 minutes, according to the time of day, and the normal speed is from 18 to 25 miles an hour. Each train has a seating capacity of 125 people, with standing room for about 50 more.
Cost. The total cost of constructing the tunnels, viaducts, stations, car sheds, and track equipment was $5,000,000, while the electrical equipment and rolling stock cost $1,000,000. The line was built with private capital. The concession runs for a period of 30 years. The company paid a dividend of 31 per cent. in 1903. The traffic in that year was 10 per cent. greater than in 1902.
The Budapest Electric Subway. Budapest, the beautiful capital of Hungary, has an electric underground railway about 2 miles in length, extending under Andrassy street-- one of the finest residential streets in the world. Work was begun on this system in 1894, and completed about two years later. It is a double-track overhead trolley subway, a little smaller in cross section than the double-track Boston tunnel, which it closely resembles in design. The side walls are built of concrete masonry and support the steel channels which, with the arches sprung between them, form the roof. The street pavement is laid immediately upon these. Through the center of the tunnel is a row of steel columns supporting the roof. The tunnel was constructed by the open-cut method, those portions of the street occupied by the work being closed to traffic.
The accompanying engravings convey a clear idea of the manner of prosecuting the work. The street is fenced off at each end of the excavation, and a fence is built down each side of the cut. The entrances are very ornamental in design, and in keeping with the neighborhood in which they are placed.
Kiosk, Budapest Subway.
Kiosk, Budapest Subway.
View Showing Construction, Budapest.
[Much of the information contained in the following description of the Paris Subway is obtained from a valuable paper read by M. Biette, Chief Engineer of the Metropolitan, before the International Engineering Congress, held at St. Louis in October, 1904. We are also indebted to M. Biette for the excellent photographs from which the accompanying half-tones were made.]
The rapid transit problem of Paris has been solved in a manner widely different from that pursued in any other great city. This remark applies to the law providing for the construction, as well as to the methods used in prosecuting the work.
Lines. The law authorizing the Metropolitan Electric Railway System was adopted in March, 1898. Lines were to be built as follows:
- From the Porte Vincennes to the Porte Dauphine.
- A circular line following the old outside boulevards.
- From the Porte Maillot to Menilmontant.
- From the Porte de Clignancourt to the Porte d'Orleans.
- From the Boulevard de Strasbourg to the Austerlitz Bridge.
- From the Cours de Vincennes to the Place d'Italie.
- From the Palais Royal to the Place du Danube; and
- From Auteuil to the Opera through Grenelle.
Franchise. The franchise was granted to the Campagnie Generale de Traction for a period of 35 years. This company was reorganized as a corporation whose only purpose should be the operation of the road, and by a State decree was called the "Compagnie du Chemin de Fer Metropolitain de Paris."
Paris- Station, Rue d'Allemagne. Station, Place de la Republique.
The City of Paris took charge of all structural work; that is, of all tunneling, excavations, and viaducts, including the restoration of streets utilized to their former condition, and of the platforms in the stations, but not of the passageways giving access to them. All other expenses-- such as those involved in the construction of tracks and electrical transmission lines, plants, and power stations, the purchasing of the necessary sites, the preparation of stairways and elevators for the stations and the cost of rolling stock, etc.-- were to be met by the company.
The fares authorized between any two points on the railway are 15 centimes for a second-class and 25 centimes for a first-class ticket.
Compensation Paid to City. A part of the gross earnings is to belong to the City of Paris, at the ratio of .05 centimes for each second-class and .10 centimes for each first-class ticket. This is to be increased by .001 franc for each 10 million passengers till it reaches .055 and .105 franc, respectively, per ticket, as the number of passengers carried increases from 140 millions to 190 millions a year.
The lines form three distinct systems, and have a total length of 77 kilometers (about 45 miles), exclusive of the spurs connecting them. The first system must be finished by March, 1906, and the second and third ten years later. All the lines will be underground, except a part of the Circular Line, and the line from the Cours Vincennes to the Place d'Italie.
City Pays Part of Cost. The city has been authorized to contract special loans amounting to 335 million francs for the purpose of defraying the expense of its part of the work. Of this amount 285 millions of francs will be needed to cover actual construction. The rest will be applied as follows: Borrowing expenses, 7 millions; cost of tearing up the streets at certain points, 28 millions, leaving a reserve of 15 millions, to be used later in the construction of branch lines and spurs. The total length of 77 kilometers is obtained by measuring the length of each line on its axis. If the side tracks, crossings, etc., are added, the total length will be 84.7 km., counting the single track for only half its actual length. The structural part of the railway will, therefore, cost the city an average of 3,400,000 francs per km. The cost to the company having the franchise is estimated at 1,500,000 francs per km., so that the cost per km. of double track is estimated at 4,900,000 francs.
View Showing Construction- Paris Subway.
Bridge Across Seine- Paris.
Appreciation of the System. The following paragraph illustrates the public appreciation of the subway system. M. Biette says: "According to the terms of the franchise annexed to the law of March 30th, 1898, the construction of the first three lines only was made compulsory, but the success following the opening of the first line was so great that it was decided to undertake the construction of the entire system.... The order in which the different lines are to be constructed was determined by the convention granting the franchise; but the City of Paris is allowed to construct more than one line at a time, provided the general order of construction is not changed. Advantage has been taken of this privilege. The new lines will increase the total length from 77 to 134 km."
In Operation and Building. At the time M. Biette's paper was read the situation was as follows: Line No. I, from the Porte de Vincennes to the Porte Maillot, the northern Circular Line; No. 2, from the Porte Dauphine to the Place de la Nation, along the boulevards on the right bank of the Seine, and the section of the southern Circular, No. 2, between the Place de l'Etoile and the Seine, now in operation. The southern Circular Line, from the Seine to the Place d'Italie, along the boulevards, had been finished, so far as the tunnel was concerned, and it was necessary only to finish the great works at the two crossings of the Seine in order to connect it with the lines in operation. These works are now under way, and will be ready some time this year. Work has been commenced on Lines Nos. 4, 5 and 6, and the preliminary plans for the construction of Nos. 7 and 8 are under way.
The number of passengers carried in the first three years was as follows: In 1901, 52,096,285. In 1902, 63,021,068. In 1903, 67,993,147.
Design of Tunnel. From an engineering point of view the Paris tunnel cannot be described as a "tube," any more than the New York Subway. The London tubes, strictly so called, are circular in section, and formed of cast-iron plates. This form is admirably adapted to the soil of London, but was not considered suitable to conditions in Paris. The engineers adopted a plan having the following characteristics: There was to be no metallic tubing, except in crossing the Seine. A double-tracked masonry tunnel was to be built and was to run as near the surface as possible. This method was considered to have the following advantages: It would be economical to construct, facilities of operation would be greater, and the stations would be easier of access. It was thought also that the danger of disturbing adjacent buildings during construction would be less. M. Biette remarks further:
"Objection to the surface plan adopted at Paris may be raised on the ground that it requires altering underground conduits, sewers, water and gas mains, electric cables, etc., which are very numerous in the subsoil of the metropolitan highways. This objection cannot be denied; but it has been possible to replace these conduits without serious trouble; and the expense incurred, although very heavy, is nothing compared to the increase in cost that the tube system would have caused to no purpose; such expenses, in any case, have no weight if the advantages of the plan adopted are considered."
Standard Section. The standard section of the double-tracked tunnel is formed by an elliptical arch, having a width of 7.10 m. and a rise of 2.07 m., supported by two side walls finished inside by circular arcs; the section is completed by an invert. The width at the rail level is 6.60 m. Where it has not been possible to follow this design a metallic roof, supported by masonry walls, has been built. The parts of the tunnels connecting the different lines are single track, the arched roof being 4.30 m. wide. The stations are arched wherever the clearance allows; metal roofs are erected when this is not possible. A standard station, whether arched or metal-roofed, comprises two side platforms 75 m. long and 4.1O m. wide. They are reached by staircases opening on the streets, and leading into underground rooms where tickets are sold. Passengers reach the nearest platform by other staircases, and those more distant by similar staircases, after crossing the railway tracks by footbridges.
Elevated Structure. The elevated part of the system consists of a metal viaduct formed by a series of separate bents of variable lengths, composed of two side beams supporting the floor system on their lower flanges. These bents, as a rule, are carried on cast-iron columns; but when necessary to secure greater stability masonry pillars are used. In order that the viaduct may not interfere with street traffic, the length of the trusses conforms to local conditions. Spans of about 22 metres have been found most satisfactory, except where longer ones are needed for special reasons. Larger spans were resorted to in crossing important streets and railroad tracks; for instance, the crossing of the Northern and Eastern Railroads, on the right bank of the Seine, required three spans of 75.25 m. each. The lower chords of the girders are straight, and the upper ones parabolic.
The trackway ballast is supported by brick arches connecting the cross-beams. This system was adopted for the purpose of lessening the vibration from passing trains, and of reducing resulting noises and tremors to a minimum. When, however, the trusswork is longer than usual and this method would unduly increase the dead weight, the track is laid directly on a platform formed of cross-beams connected by stringers covered with metal plates. The minimum distance between the surface of the street and lower chords is 5.20 m., this clearance being sufficient to permit the passage of vehicles with high loads.
Map of Paris Metro Routes.
Elevated Stations. The elevated stations are constructed on the same plan as the viaducts, each having a total length of 75 m. Staircases lead from the street to intermediate platforms, where the ticket offices are placed, and from there to the station platforms.
As a rule, passengers have to change cars at junctions and points of transfer. This plan was introduced in order to avoid the danger of collisions in switching trains between lines, and loss of headway on given lines. Loss of time at terminals is avoided by the provision of loops, which permit trains to be moved directly from points of arrival to points of starting.
Two kinds of masonry are used in the underground work, sandstone and concrete; the first being employed for arches, and the second for side walls and floors. All visible facings inside the stations are covered with white tiles, or enameled brick; all other work with cement. All metal work, such as bridges, roofs, and stations, are made of soft rolled steel having an elongation of 23 per cent. under a breaking load of 43 kg. per square mm. of section.
The preliminary work, such as diverting sewers, water mains, and other conduits, is let out by public tender; this system being compulsory in France for public undertakings generally. The plan is described as follows:
Method of Building. "Each line is divided into sections, generally about 1,000 m. long, and never more than 1,500 m. long for underground work. For the elevated parts the length of the sections is limited to about 900 m. Each contractor has a time limit fixed for the completion of his work, and generally this limit is calculated by allowing one month for 100 m. underground, and three months extra for the preliminary organization of the plant. A large premium is given for each day gained on the limit fixed, and an equal fine imposed for each day of delay. By this arrangement the work is completed in a comparatively short time. Line No. 1, the first built, with a length of 10.5 km. (about 7 miles), was finished in 17 months of actual work, and Line No. 2, on the left bank of the Seine, with a length of 9.4 km., was finished in 18 months."
"On each section there is, generally speaking, only one point at which ground is broken; but other secondary points are sometimes authorized, as at stations or other works of special importance. At such points the contractor sinks vertical shafts in which electric elevators are installed for hoisting excavated material, and lowering materials of construction. In the ordinary construction of the tunnel the method followed is nearly always to construct the arch first, the side walls next, and then the floor."
"For stations, however, and arches of special works, where the span is more than 10 m., the side walls, Or abutments, are first constructed in galleries, and then, as the case may be, the arch is constructed, or the metallic roof put in position; the core of the tunnel is then excavated, and finally the masonry for the floor is laid."
Shield Not Applicable. At first it was expected to construct Line No. 1 by means of a shield of the Brunel type. It was expected that the shield plan would do away with most of the breaking up of the streets. But better results were not obtained with it than with timbered headings. Where the design calls for a strong lining like cast-iron, and where progress is made through material of uniform consistency, the shield presents marked advantages; but in ground of a varying character, such as the sub-soil of Paris, the results are not so satisfactory. In that city, excavations, bad fillings, foundations of old buildings, and the like, which prevent the regular advance of a mechanical device, are encountered. In ground of that kind it is often necessary to increase the strength of masonry, either by reducing the outside cross-section or by increasing the thickness. Such modifications are difficult to make when the shield is used.
Advancing Headings. The heading was advanced by digging out the highest part of the tunnel and constructing the arch. In some localities good results were obtained by opening two headings simultaneously, one at the top and the other at the bottom, the last one being kept in advance of the first. The lower heading is used to carry out the earth, and the other to bring in the materials for the arch. The arch masonry is built in sections 3 m. in length. In solid ground the bench is nearly all taken out before the walls are begun; but in soft earth trenches of variable dimensions are cut before the bench is removed. When the arch and retaining walls have been completed, grout is forced behind the masonry so as to fill any spaces between the masonry and earth, these injections being made through holes left in the masonry during construction. The holes are provided over the whole surface of the arches and one-half meter down below the springings.
Removing Earth. One of the most difficult problems to solve, in the construction of the Metropolitan Railway, was the removal of excavated material and the carrying in of materials of construction. If it is considered that when a bench is removed an average section produces from 800 to 1,000 cu. m. per 24 hours, it is easy to understand how difficult it is to remove such amount of earth by means of ordinary carts in the center of the heavy traffic of Paris. Methods more modern, more rapid, and more economical were sought. For instance, in the central part of Line No. 1, running at a short distance from the Seine, the contractors did not hesitate to build special galleries, many hundreds of yards long, in order to connect the tunnel with the Seine, and thus allow the removal of the excavated material by boats. At other points the street car tracks connecting with the suburbs of Paris have been taken advantage of. Spurs have been constructed from these tracks to elevators in the working sites so as to allow the direct removal of excavated material without reloading. On Line No. 3 the earth coming from the central sections near the St. Lazare Station, the Opera, and the Bourse has been carried beyond Paris by means of a temporary spur constructed specially to connect with the Ouest Railroad.
Work at the Seine. Lines 2 and 8 cross the Seine twice, and Lines 4 and 6 once. Lines 4 and 8 pass underneath the river through metal tubes. The Passy Viaduct is doubledecked, one deck for carriage traffic and the other for trains. It occupies the site of a foot bridge connecting the Boroughs of Passy and Grenelle. It was necessary to do away with this bridge, but it was also essential not to cut the connection between the banks. The bridge was, therefore, moved back, parallel to itself, a sufficient distance to free the working sites of the viaduct. This bridge consists of two similar parts which correspond to the two arms that form the Seine at this place. The part above the wider arm had a length of 120 m., a width of 6.50 m., and a weight of 320 tons; the other had a length of 90 m., a width of 6.50 m., and a weight of 240 tons. Two methods were employed in moving the two spans. The wider arm was placed upon rolling timber platforms, supported on piles, and moved by means of windlasses, the distance being 30 m. The entire operation was performed, in four hours, without the slightest trouble, and without having interrupted in the least the traffic on the river. The other span was floated to its position on barges.
Difficulties Encountered. The difficulties encountered by the engineers of these roads were of a type varying widely from those confronting the designers of underground roads in other large cities. The sewer, water, and gas pipes found in other works were here present, but a greater obstacle was the diversified character of the ground, which possessed different qualities in each section, and compelled the changing of the plans almost continually in order to overcome new troubles. One notable instance was as follows: Line No. 3 connects with the Circular Line, on the right bank of the Seine, at the Boulevard de Courcelles, between the Boulevard Malesherbes and the Avenue de Villiers. As originally planned this connection was to have been on the level, so that for a certain length the tunnel was made 18 m. wide, in order to accommodate four tracks and junctions between the two lines for handling the empty cars. But it was decided to provide for a possible extension of No. 3 toward the periphery, and as this could only be done by passing under No. 2, it became necessary to deepen the tunnel common to both lines, and to build at once the crossing of this line under the side wall of the great 18 m. arch. This task was done by alternating cross trenches, each 2 m. wide. The crossing under the other side wall of the arch, having a bad slanting direction, two galleries, joined together by a single track, have been substituted for the standard type of tunnel.
Another difficulty may be mentioned. This was caused by the formation of the sub-soil met in the construction of Line No. 3 at the Terminal Menilmontant, under the Avenue Gambetta and the Rue Belgrand. It is composed of gypsum marl that forms the bottom of a basin filled with clay or fine sand, both being impregnated with water. The water bearing sand forms a particularly troublesome element. The work was done as follows: The side walls were first undertaken in such a way as to obtain the drying of the thin sand. For this purpose a large number of wells were sunk from time to time through the layer of sand to the marl. These wells, sunk with all the care necessary, were provided with permanent means of drainage, and by their continued operation caused the semi-fluid ground to become firm enough to permit the construction of the tunnel.
Up to the present time the construction of the Metropolitan Lines has progressed rapidly; and a considerable advance, viewed from the length of actual construction, on the time allowance granted by the franchise, is noticeable.
The care taken to provide in Paris a rapid transit system that will serve the public needs admirably will be appreciated by those who carefully study the map of Paris given herewith, and the rapid transit lines laid down upon it.
It would be impossible, however for anyone to know how little the public were inconvenienced during the construction of the lines already completed, except by observation on the spot. A visitor to Paris, during the time of construction, might have gone about the city for days and have remained in ignorance of the fact that the work was going on.
First Road. In 1882 Parliament granted to the Glasgow City & District Railway a franchise to connect the two lines of the North British Railway, so that some of its trains could run through the city. This line is 3.12 miles long, and has four stations. It was opened in 1886. One mile was built by tunneling; 3,483 feet by cut and cover; 3,942 feet in open cut between retaining walls; 330 feet were under bridges, and 342 feet under the Queen street station, the main terminus of the railway. The road is double track. The tunnel is a brick arch, with a clear span of 26 feet in rock, and 27 feet in other material. On the urban portion of the line there are four stations, all of which are wholly or partly open at the top. The tunnel part of the road cost £34,000 per mile.
In 1888 the Caledonian Railway was authorized to construct the Glasgow Central Railway to connect its existing lines. This is a double-track road, 6.4 miles in length. In section the tunnel is a brick arch, supplemented with a concrete invert wherever the ground is soft. Where it was desirable to have the structure as near the surface as possible, a flat roof of plate girders was substituted for the arch. Most of the cut and cover work was done along Argyle street and the Trongate, the most crowded thoroughfares in the city. Before commencing the railway, it was necessary to rearrange all the street pipes and sewers for a distance of 2-1/4 miles.
Building Restrictions. In the act granting permission to build the road, important clauses were introduced limiting interference with street traffic. Streets like Argyle were not to be torn up except between 12 P.M. Saturday and 5 A.M. Monday. Excavated material was removed through special openings, limited in area to 50 by 17 feet, and placed not nearer to each other than 200 yards. Streets of minor importance were torn up a portion at a time, but the surface had to be restored inside of three months.
Including those at the ends and the one at the terminus of the Maryhill Branch, there are 12 stations at average intervals of half a mile. Wherever possible the stations were made uncovered, only three being entirely roofed over. Five are partly underground, and four are entirely in the open. In general the stations are 600 feet in length and 47 feet in width, thus providing two platforms 13 feet wide.
Claims for Damages. Many claims for damages were made during the construction, but most of the suits were decided in favor of the company, the exceptions being cases where the time allowed for keeping the streets open was exceeded. Under the law in England, no damages can be collected for commonplace or ordinary obstructions, the principle being that the right to make such obstructions is a part of the franchise, even though the company selects the site. A suit for damages was brought against the City & South London Railway because it had established its power station on property next to an orphan asylum, thereby rendering the latter uninhabitable. The decision was in favor of the defendant, on the ground that the company had statutory power to carry on the undertaking, and to do anything necessary to accomplish its object, even if it proved a nuisance, provided it exercised reasonable care and skill.
The total contract price for the work was £1,900,000, or about £300,000 per mile. The road itself, without equipment or station fittings, cost £1,020,000.
Glasgow District Subway. In 1891 work was begun on the Glasgow District Subway, a line built for purely local traffic and having no connection with any other road. It is a two-track circular road, 6-1/2 miles long, the route as far as possible following the street lines. The two tunnels are 11 feet in diameter, and are built of cast-iron plates. Each station, of which there are 15, is 150 feet long, with island platforms 1O feet wide and stairways 6 to 8 feet wide. Exclusive of land and equipment, the road cost £115,000 per mile.
Glasgow Harbor Tunnel. The Glasgow Harbor Tunnel crosses the bed of the Clyde, and provides passageway for vehicles and pedestrians. It comprises three tubes, having a shaft at each end 80 feet in diameter and sunk 75 feet below the surface. Each tube is 16 feet in diameter in the clear and 720 feet long. Two of the tubes are paved for vehicles, the third being for foot passengers only. In each shaft are six elevators for handling vehicles and passengers.
Boston was confronted with a peculiar transportation problem. Numerous radiating lines converged on a few streets at the center of the city. Some of the busiest thoroughfares were so occupied by electric cars that vehicular traffic was greatly interfered with. Many of the streets in the congested district were narrow and crooked, and were bordered by business establishments requiring the employment of many wagons. The problem was not so much one of providing rapid transit facilities as of relieving the streets within an area about one mile long and not much more than a quarter of a mile wide. The solution was reached by building a subway through the congested district, and placing all the trolley lines within it. The road has been finished, the congestion relieved, and, the streets returned to the unrestricted use of pedestrians and ordinary vehicles. A comprehensive idea of the old and of the present state of affairs may be formed from an examination of the two engravings, given herewith, showing the conditions of Tremont street before and after the improvement.
Boston Elevated Company. The Boston Elevated Railway Company was incorporated in 1894 with a capital of $10,000,000. This company was to build and operate certain lines of elevated railroad in Boston and vicinity. The company deposited, with the city Treasurer, bonds to the amount of $500,000 to indemnify the city for any damages. It is to be assessed, and to pay taxes the same as any street railway. On and after the first of January, 1907, the company is to pay a franchise tax of not less than 1 per cent., nor more than 5 per cent., of its gross earnings, as the Board of Approval may decide. This tax is to be paid into the treasury of the Commonwealth, and distributed to the different towns and cities affected, in proportion to the mileage operated in each.
This road must not be confused with the lines authorized by the Boston Transit Commission at a later period. It controls the elevated roads of the city, but has nothing to do with the subways, with the exception of a short section constructed solely for its own exclusive accommodation, as will be explained presently.
Park and Tremont Streets--Boston. Before Subway Construction.
Park and Tremont Streets--Boston. After Subway Construction.
Boston Transit Commission. The Boston Transit Commission was created by an act approved July 2, 1894, and accepted at a special election held July 24, 1894. The commission is composed of five members, three of whom were named in the act, and two appointed by the Governor. The term of office was originally 5 years, but this was afterward extended to the first day of July, 1906. If the term of the commission should expire before the completion of the work, the duties are to be assumed by the mayor, city engineer, and treasurer. Any vacancy in the commission is to be filled by the mayor, subject to the approval of the board of aldermen. The act names the routes along which the commission may build subways, but the commission cannot extend these lines or construct new ones; it has no initiatory power. Provision is made for building a bridge over the Charles River. The commission may, on or before the completion of the subway, grant locations for tracks in it to any street railway company, and "shall order all surface tracks to be removed from Tremont street, between Boylston street and Scollay Square, and from Boylston street, between Park Square and Tremont street; and may order any other tracks that, in its opinion, have become unnecessary by the construction of said subway and tunnels, and which are above said subway and tunnels, or within a distance of 1,000 feet from any entrance to said tunnels, to be removed from the streets." Electric wires may be placed in the tunnel at such compensation as may be determined by the commission.
Expenditure Limited. The work is to be paid for by bonds issued by the city treasurer, not to exceed $7,000,000, and such further amount for the Charlestown Bridge, in addition to the $750,000 appropriated by the city council, as may be necessary for its completion. A sinking fund is created into which are to be paid all premiums from the sale of bonds, and all proceeds from sale of lands or rights to use the subways.
On the completion of the subway the commission may contract for the use of the tracks to any street railway company for a period not exceeding 20 years, the compensation to be determined by the commission, subject to the approval of the railroad commissioners.
Four-Track Construction- Boston Subway.
Park Street Station- Boston Subway.
Additional Routes; Agreement With Boston Elevated. The act of 1902 provided for the construction of an additional subway from Broadway and Washington street to Court and State streets, and thence to Adams Square, Haymarket or Causeway street, together with connections with the East Boston Tunnel and the existing subway. This further subway was to contain two tracks exclusively for use by elevated trains, and two tracks for surface cars. Within 90 days after the passage of the act, the commission executed with the company (Boston Elevated Railway Company, mentioned above) a contract for the exclusive use of this short section of the subway for a period of 25 years from the date of opening. The annual rental is to be 4-1/2 per cent. of the cost of the tunnel. The cost of the tunnel includes all expenditures for construction and acquisition and interest at the rate of 3-1/4 per cent., per annum, on the debt incurred in construction prior to the beginning of the use. If the company execute the contract, it may, subject to the approval of the Board, construct certain additional lines of elevated railway. Upon the completion of the tunnel the company must remove its elevated trains from the existing subway. The commission had granted the use of the subway to this company as a matter of convenience for the public, and no permanent rights had been issued to the Elevated Company for such use. The arrangement was only of a temporary character, to be annulled upon the completion of the short section referred to.
Agreement With West End Company. In December of the same year a contract was made with the West End Street Railway Company, controlling the surface lines of the city, by which that company was granted the exclusive use of all the subways then constructed and those to be constructed in the future. The term of the grant is 20 years. For this privilege the company pays the city the sum of 4-7/8 per cent. of $7,000,000, the compensation to begin when the company assumes control. The company also agrees to pay an additional sum of 5 cents for each passage made through the subway by a car not exceeding 25 feet in length, and a proportionately greater rate for each car of greater length. All equipment furnished by the company is to be the property of the company as long as it shall continue to operate the tunnel; this equipment is to be purchased by the commission, at a fair valuation, if the company ceases operations. The company is to make all repairs.
No Grade Crossings. The routes built and building are shown on the accompanying map. The station at the corner of Boylston and Tremont streets is so designed that there is no grade crossing of tracks on which cars run in opposite directions, the separation being effected by means of a sub-subway for the southbound Tremont street cars. At Park street is a loop around which all cars pass that do not run beyond this point. There are four tracks under Tremont street along the line of the Common, these taking the place of the two surface tracks. Bids for the construction of Section 1, which included all that portion of the subway on Boylston street to West street, with the exception of the station at the corner, were opened March 20, 1895. The first spadeful of earth was removed on March 28, 1895.
Map of Boston Routes.
Design of Tunnel. The incline is an open avenue descending from the surface of the ground opposite Church street to the subway portal. The length of the incline is 318 feet, and it descends about 17 feet in that distance. It has granite walls, underneath and back of which is concrete masonry, with all the deeper portions supported on a pile foundation. The two-track subway is 24 feet to 24 feet 8 inches in width inside, 16 feet 6 inches in height along the center, giving a clear height of 14 feet above the rails. The side walls are composed of 15-inch I-beams spaced 6 feet apart, standing on granite footing-stones. The space between the beams is walled with concrete, in which the beams are bedded. The roof is supported by 20-inch I-beams spaced 3 feet apart, the intervening space being bridged with brick and concrete masonry. The four-track subway is similar to the two-track, with the exception that its clear width is 48 feet, and that it has a row of columns along its center.
A provision of the act required that the commission "shall so conduct the work of construction that all streets and places under or near which a subway is constructed shall be open for traffic between 8 o'clock in the forenoon and 6 o'clock in the afternoon."
Method of Building. The method of building the subway will be understood from the following extract from the specifications:
"Trenches about 12 feet wide shall be excavated across the street, to as great a distance and depth as is necessary for the construction of the subway. The top of the excavation shall be bridged by strong beams and timbering, whose upper surface is flush with the surface of the street." [These beams usually consist of hard pine 10 inches by 8 to 12 inches, 20 feet long, placed side by side lengthwise of the street. Two or more 6-inch I-beams are used for supporting each rail of the street railway. The ties of the railway are usually under these beams and fastened to them with bolts. The surface of the beams is covered with plank, precisely flush with the paving of the street.] "These beams shall be used to support the railway track as well as the ordinary traffic. Portions of the bridging can be removed day and night. In each trench a small portion, or slice, of the subway shall be constructed. Each slice of the subway thus built is to be properly joined in due time to the contiguous slices. The contractor shall at all times have as many slice-trenches in process of excavation, in process of being filled with masonry, and in process of being backfilled with earth above the completed masonry, as is necessary for the even and steady progress of the work toward completion at the time named in the contract."
This method does not disturb the railway tracks at all, and leaves the whole surface of the street entirely free, in the day time, for normal use.
Masonry Tunnel. The masonry tunnel is built with concrete side-walls and brick arches that spring from one all to the other. The arches have heavy concrete backing, and are further strengthened by vertical I-beams about 6 feet apart, imbedded in the walls, each pair of opposite beams being connected at their top by a tie-rod which passes just above the interior crown of the arch. The tunnel is 12.25 feet wide in straight sections, and considerably wider at the curves. The height from the invert to the crown is 16 feet. The side walls are 2 feet in thickness. The bell-mouth, where two tunnels join, is 30 feet wide and has a clear height of 21 feet. The side walls are 4 feet 10 inches thick and the brick arch 28 inches thick. The arch is strengthened by tie-rods 2 feet apart strained against washer plates. The bell-mouth grows smaller in cross-section until it unites with the normal wide arch of the subway, which has a span of 23 feet and a height of crown of 17-3/4 feet.
Roof Shield. A roof-shield, similar to an ordinary shield, except that the lower half was omitted, was used successfully on a portion of the work. It was an arch-like structure, 12 feet long, with a rise of 8 feet 7-1/4 inches in its outer span of 29 feet 4 inches. It was built around two arched girders 3 feet 8 inches deep, placed 4 feet apart, leaving 4 feet of overhanging plates at front and back. The space between the girders was divided into 10 compartments, in each of which was placed a hydraulic jack. The track supporting the shield was placed on the side walls, cast-steel shoes being provided for the shield to rest and move upon. The greatest freedom and accuracy of manipulation were found possible with this arrangement, the control of the valves being effective in correcting slight changes in direction, overcoming uneven resistances, and in traveling around curves. As the shield moved forward the 1-inch space over the arch masonry, due to the thickness of the shield plates, was filled with cement grout (pumped through pipes left in the brickwork), so as to make a close connection with the earth above. The material passed through was compact clay and sand, and loose sand and gravel, with occasional boulders up to 4 feet in diameter. This is perhaps the first instance of the use of a shield in connection with a masonry tunnel.
The walls of the stations are lined with enameled white brick. The steel columns are encased in concrete and painted white. The brickwork, and the exposed steelwork of the roof, are also painted white. The staircase walls are lined with white brick, and the roofs are made of metal and glass.
Daily Traffic. Prior to 1897, when all the Tremont street car traffic ran on the surface, the utmost limit of capacity of the surface tracks was found to be about 200 cars per hour each way. The rate of progress was often not more than two miles per hour. In October, 1898, one month after the complete transfer of the surface traffic to the subway, the number of cars passing freely each way at the same point within the subway, during the hours of greatest travel, was 282, the rate of speed, including stops, being between 7 and 8 miles per hour. This meant that the cars between the Public-Garden entrance and the Park street station, moved on a fixed schedule time of 4 minutes in the subway, instead of an uncertain time on the surface varying from 10 to 20 minutes.
When the Park street station was opened the Commission was confronted with a problem apparently without a counterpart in steam or street railway practice. Between the hours of 4:30 and 6 in the afternoon the outgoing platform of this station was served by about 180 cars per hour. These belonged to more than 20 different routes, and came to the platform without any fixed order. The passengers did not know what cars were coming nor where they would stop. Dire confusion was the result. The trouble was obviated by the introduction of a large indicator upon which just before the arrival of a car, the name of the car and the location of its stop were shown.
East Boston Tunnel; Methods. The East Boston tunnel extends from Maverick Square, East Boston, under the harbor to the city proper. It carries two electric railway tracks. The East Boston approach consists of an open incline 139 feet long, and a wide-arch subway 680 feet long. The tunnel portion has a total length of 4,430 feet. Under the harbor the tunnel is 20-1/2 feet inside height by 23 feet wide. The tunnel was excavated by means of a roof-shield, as previously described, compressed air being employed to prevent entrance of water. In building the tunnel the invert was put in and the side walls carried up to within 16 inches of the springing line of the arch. The walls were terminated at this height in order to serve as foundations for the tracks upon which the roof-shield was to run. Side drifts, 8 feet square, were dug in advance of the shield, and then the core was taken out and the invert and side walls put in. Curved steel ribs made of 10-inch channels, spaced 30 inches apart, were used as centering for each ring of arch. After lagging had been placed on the ribs, the concrete was put in. The final keying up of each ring of the arch was done through two holes, about 13 inches in diameter, in the rear girder, at the top of the shield. Curved sheet-iron troughs were extended from these holes to the top of the arch. Concrete thrown into the troughs was pushed into the unfilled space at the crown of the arch. As soon as one ring of arch had been finished, the shield was pushed forward 30 inches and another ring put in. The space left vacant over the completed ring by the advancing tail-piece of the shield was filled with grout forced through a vertical pipe placed at the crown of each ring. This was probably the first successful example of fresh concrete work in connection with the shield method.
Cost. The following is a summary of the cost of the several works up to June 30, 1904:
|East Boston Tunnel||2,744,088.01|
|Boston Tunnel and Subway||156,310.23|
Boston Elevated Roads. The elevated railroads of Boston, controlled by the Boston Elevated Railway Company, extend in a north and south direction through the business portions of the city. When the present extensions shall have been completed it will extend from Forest Hills on the south, through the city to Charlestown and East Boston on the north and east. The present system, which is elevated throughout, passes along the docks through Atlantic avenue.
As we have already explained, the Transit Commission is building a tunnel under Washington street for the exclusive use of the elevated road; this and the East Boston tunnel under the harbor have been leased to the elevated company.
Bell Mouths Under Tremont Street- Boston Subway.
Chicago has inaugurated, and is now rapidly extending, a system of tunnels that bids fair to have a marked influence upon the rapid transit problem in that and other cities. The plan is original in its design; comprehensive, in that it covers the congested district, and, as far as may be judged at the present time, effective, in that it provides the desired relief. The fundamental idea has been to place the transportation of merchandise, mail, and express matter, and all supplies and refuse, in tunnels, and in that way reserve the streets for the exclusive use of the people. It is evident that such a scheme, in order to be thoroughly successful, must cover the district perfectly; it would fail if any portion, however insignificant, were omitted. Every building, the occupants of which require material of any description from without that particular territory, must be reached by the system.
Congested District. The business center of Chicago occupies an area of about one and a half square miles. Within this space are the great department stores, the office buildings, the newspaper offices, some large factories, and terminals, including six freight depots for 25 trunk lines entering the city. In addition to all this, the district is enclosed in a loop formed by four converging elevated roads. Some conception of the condition may be formed from the fact that the teaming, necessary to the transfer of goods in this district, has grown to greater proportions probably than in any other city of the world, regard being had to the space occupied. On thirty-two miles of streets, the daily movement of merchandise averages about 112,000 tons. During the busy hours as many as 1,000 teams have been counted passing a street corner in an hour. Fortunately for those advocating the freight tunnel plan, the streets, as shown upon the accompanying map, are straight and laid out at right angles.
The following item from a Chicago paper clearly, although facetiously, outlines the project:
Chicago Subway Defined. "What the subway means to Chicago: Clean streets, pure air, sunlight for the people, underground subway for freight traffic; just the reverse of New York and London, where the people are put underground, and teaming and trucking given the preference. Coal, ashes, dirt, excavations from building sites, offal, etc., taken off the streets and hauled underground. All the dirt and annoyance are abolished. Every building in the business district is equipped with tunnel connections, and thus brought into direct communication with every railroad and steamship line in the world. Freight, merchandise. and fuel are hauled in; ashes, dirt, and refuse hauled out. Uninterrupted free traffic on the surface for the people who walk, drive, or ride in surface and elevated cars. The streets for the people; the tunnels for merchandise, coal and freight."
The inception of this project was probably due to a strong public feeling that the charges for telephone service in the city were too high. Taking advantage of this feeling, the Illinois Telephone & Telegraph Company was incorporated, and granted permission to build tunnels and conduits under the streets for telephone wires. This was in 1899. In 1903 the terms of the charter were broadened so as to include apparatus for the transmission of newspapers, mail matter, parcels, merchandise, coal, etc.
Ordinance. The ordinance of 1903 provides that at the expiration of the charter in 1929 "all tunnels and conduits heretofore constructed, and all tunnels hereafter constructed, under said ordinances, shall, without the payment of any consideration, become and be the absolute property of the city of Chicago, free from liens and incumbrances."
The ordinances contain the following provisions: The trunk or main line tunnels must not be more than 12 feet 9 inches in width and 14 feet in height; the small tunnels not more than 6 feet in width and 7-1/2 feet in height. The crown of the tunnels must not be less than 19 feet below the city datum. The company must lower or remove its tunnels if the city decides to build water tunnels or subways with which they would interfere. Space must be reserved, in each of the tunnels, for the use of city telegraph, electric light, and telephone wires. The company has the right to connect up any of its tunnels with the lots of private owners abutting on such streets, and also with the branch offices or delivery stations of said company, by proper passageways or connecting tunnels. The company may lease its works to another duly authorized company, but it shall not maintain or operate cars or vehicles of any kind for the conveyance or transportation of passengers, nor shall it have the right or authority to lease space in its tunnels to any person, firm, or corporation to carry passengers in any manner.
The city reserves the right to regulate all charges and rates for the services rendered.
Map of Chicago Tunnel System.
Duration of Franchise; City To Purchase. At the end of 20 years from the granting of the franchise, the city may purchase the entire property and equipment, with the exception of the wires necessary to the carrying on of the telephone business; but the telephone company must pay a reasonable rental for the use of the tunnels. The city is to pay in cash the value of the property as determined by three appraisers in the usual way. The appraisers, in determining the fair cash value of the property, "shall not take into consideration its earning power or the value of any franchise or license, but shall allow for the property the then cost of duplication, less depreciation."
If, at the expiration of the grant, the city should not desire to purchase nor to operate the tunnels, the privilege is to be granted to the corporation making the most advantageous proposal. If the proposal of the Illinois Telephone & Telegraph Company is not as advantageous as that of some other corporation, such other corporation may purchase the property at an appraised valuation. For the privileges granted, the company must pay to the city in January of each year the following percentages of its gross receipts for the preceding year: "For the first ten years of the grant, 5 per cent.; for the second ten years of the grant, 8 per cent; and for the balance of the grant, 12 per cent. On all gross receipts the company derives from the rental of space in its tunnels and conduits it shall pay into the city treasury 20 per cent. annually."
Penalties. If the company fails to complete the work authorized by the franchise within 5 years, it shall pay to the city $200,000 within 60 days after the expiration of the 5 years. In case of failure to pay this amount within the time specified, the company forfeits "all rights acquired under this ordinance, together with its plant and equipment."
If the company fails to construct and operate 50 miles of tunnels, within 1O years from the passage of the ordinance, it forfeits its plant and equipment. Within 5 years it must also have a telephone equipment adequate for the service of 20,000 subscribers, or forfeit its plant.
Illinois Tunnel Company. The original company has been succeeded by the Illinois Tunnel Company, which now acts as both constructing and operating company. Twenty-eight miles of subway have been finished, and, when fully equipped, 60,000 tons of freight can be handled daily. The longest line is about 1 mile. It lies under Wabash avenue, one block west of the lake front. There are eight principal passages, one under each street parallel with Wabash avenue and west thereof, making nine north and south tunnels in all, with four secondary tunnels running in the same direction. At right angles with these are 15 tunnels under the cross streets. The accompanying engravings show the form of the tunnel, and the switches and connections at the intersections.
Freight Train At Street Intersection- Chicago.
Train At Street Intersection- Chicago.
Typical Street Intersection- Chicago.
Typical Distributing Station- Chicago.
Method of Building. The work was done by what is known as the pneumatic system, in which the air-lock of the ordinary pattern is placed in the completed section, and air at from 5 to 7 pounds pressure carried in the heading. This method was not absolutely necessary, as the soil was of such a nature that it would stand without caving or swelling.
Following closely all excavation work, channel-iron ribs were placed in position, with lagging behind them. Concrete was then rammed in between the lagging and earth, and in this way every void was completely filled. The lateral conduits were built with a 13-inch invert and 10-inch walls. The trunk system was constructed with 21-inch invert and 18-inch walls.
In order to prosecute the work smoothly and rapidly, the excavated material had to be disposed of without delay. This was accomplished by the use of tramcars on a track of 14-inch gauge. A line of double tracks was laid, and the cars were hoisted by elevators up the shafts to a headhouse built on the curb line. The material was dumped into wagons standing on the street. Most of the hauling away was done at night to avoid interference with street traffic. The first 12 miles of tunnel were built without causing a complaint from any source, and without accident of any kind. Over 12 miles of tunnel were completed in ten and one-half months of actual work.
Connections with buildings for telephone service are made by drifts, 3 feet in diameter, from the tunnel to points within the curb line, and by driving 2, 3, 4, or 5-inch pipes to meet the drifts. In this way the necessary cables are taken into the buildings of subscribers.
Third Rail Traction System. The four-way intersections have curves of 20-foot radius, the sharpest curves on the main line being 16-foot radius. The track is 2-foot gauge laid with 56-pound rails. The Morgan third-rail traction system is used. This consists of a perforated steel plate, 1/2-inch thick by 4 inches wide, forming a rack, which is bolted between two lines of timber stringers, as shown in the engraving. These both protect and support the rack. Engaging with the teeth formed in the rack is a gear driven by the motor of the locomotive. By means of this construction the rack serves both for traction and as a third rail conductor. The current is taken up by the teeth of the driving gears and led to motors geared to the axles. The track rails are used for the return current. A speed of between 15 and 20 miles per hour is attained.
Cars. The cars are of steel construction throughout, and are 12 feet in length over all. They are of the double-truck, eight-wheel type. The design is such that a car can be used either as a flat car or gondola, and the contents can be dumped without removing either the sides or ends. The box car is 48 inches wide, 10 feet 6 inches long, stands 63 inches above the rails, and has a capacity of 30,000 pounds.
The district consumes 4,000,000 tons of coal annually. Contracts have been made for hauling the supply for many of the large buildings, and for the removal of the ashes, the contracts being in force for periods of a year. The Post Office Department has a contract with the company for the handling of mails between the general post office, the sub-stations, and the railway stations, to run for a period of 5 years, the consideration being approximately $175,000 per annum.
The company has an authorized capital stock of $30,000,000, and a bond issue of like amount. Of the $30,000,000 in bonds, $15,000,000 has been issued, the remainder being held in reserve for future extensions of the plant.
Passenger Subway. Chicago is now considering the advisability of building a passenger subway system, having the following as it main features:
An underground subway system making it practicable and serviceable to put in operation a one-fare system without the issue of transfers; no grade crossings; cars to be run from the different divisions of the city to other divisions as may be convenient for the people; foot walks ten feet wide along all lines; a system that will take care of new sewers, a high pressure water system, and a storm-water system.
It will be seen that the subway work already done in Chicago, and the suggestions for further developments, present features radically different from anything so far attempted in other cities in our land and abroad. The practical merits of the plans-- those already accomplished and those proposed-- are so evident that one cannot but believe that they will be followed elsewhere in greater or less measure. It cannot be supposed for a moment that trains for the transportation of passengers will be run on the surface, because of the danger to other traffic. It can hardly be supposed that the people of great cities will be content with elevated systems involving noise and the disfigurement of streets. It would seem that underground ways must come into common use, not only for passengers and for freight, but also for sewers, for water pipes, and for conduits of different kinds. In this way, and in this way only, can the surface of streets be reserved for ordinary traffic, and the incessant breaking up of pavements avoided. For not only are the streets of our great cities, and those of European cities, greatly overcrowded by traffic, but here and there serious breaking up of pavements is going on all the while. The cases, indeed, are not infrequent when different gangs of men are employed on the same street-the one replacing pavement, the other opening the ground for some different purpose.
Routes. As we have just mentioned, the congested section of Chicago is embraced in a small area on the lake front near the center of the city. The elevated railroad systems cover the outlying districts to the north, west and south; all of the roads meeting in a loop encircling the business portion. This provides for the quick handling of all traffic from three cardinal points, and for the unlimited extension of the residential districts in like directions. These features, in combination with a flat country in each direction, vastly simplified the elevated problem. The absence of heavy grades and sharp curves is unique in elevated railroad practice.
The elevated roads started with the incorporation of the Chicago & Oak Park Elevated Railroad, in August, 1892. This was formerly known as the Lake Street Elevated Railroad. The franchise carried the right to build a double-track elevated structure from Wabash avenue and Lake street west to Wisconsin avenue and South Boulevard. Since then the following elevated roads have been constructed:
The South Side Elevated line, with two routes extending directly south. This road is being extended by east and west lines at Thirty-ninth and Sixty-first streets.
The Metropolitan West Side line, with roads to the west and northwest.
The Northwestern Elevated, with a line due north. This road is extending its system further to the north.
The loop where all the roads meet in the city is controlled by the Union Loop Company, which leases the use of the loop to the other four roads.
Philadelphia is now engaged in the construction of a comprehensive system of rapid transit. The conditions there are more favorable than those in any of the other cities we have mentioned. The city was originally laid out regularly. The streets running north and south are parallel, and those running east and west are at right angles to the others. Two of the streets, Market and Broad, divide the city east and west and north and south, and are of unusual width. These features permit of rapid transit lines that are straight, and provide convenient points for diverging lines.
Act of Assembly. The legal foundation of all the corporations created for the purpose of constructing and operating elevated systems of municipal railways in Pennsylvania is the Act of Assembly of June 7, 1900. Section 1 provides that any number of persons, not less than five, three of whom are citizens of the commonwealth, may form a company for the purpose of constructing and operating passenger railways, either elevated or underground, or partly elevated and underground, and for the collection and distribution of mails of the United States; permission to erect or construct to be obtained from the local authorities of the city in which the road is to be operated.
Section 2 provides that the charter shall be subscribed to by at least three of the corporators, who shall certify, in writing, to the Governor, the name of the company, number of years it is to be continued, and other details in regard to the road, amount of capital stock, etc. This section prescribes also the powers and privileges of the corporation. These are the usual privileges of such a body; but, in addition, power is granted to sell or lease any road or franchise, or any parts thereof, to other companies, or to acquire other roads and franchises.
Section 8 gives such corporations rights of eminent domain.
Section 12 provides that construction shall be begun, in good faith, within two years, and be completed within five years thereafter.
Elevated or Underground. A supplement to this act enlarges the power of such corporations, so that they are authorized to build either an elevated or underground, or both an elevated and underground railway, over the route described in their charter, after having obtained the consent of the local authorities.
Corporations, incorporated under the original act, were given power to construct branches and extensions. The amendment of March 25, 1903, gave them power, with the consent of the local authorities, to abandon any portion of the road, or to merge with other companies, and when two or more roads shall be so merged, the commencement of the work, in good faith, upon any part of the route, on any of such merged roads, shall be a commencement upon all tie merged roads, within the meaning of the act; provided that the work shall be completed within five years upon all the merged roads, unless the time for such completion shall be extended by the proper local authorities. This was an important addition, for the charters of a number of the following mentioned elevated and subway lines would have been forfeited if it had not been for this provision, as work, even vet, has not been begun on them.
Market Street Company. The Market Street Elevated Passenger Railway Company was authorized to build and operate an underground road from Delaware avenue on Market street, around the Public Buildings under any and all streets bounding the same, and continuing on Market street to the county line, with the right to come out upon the surface of Market street west of Twenty-second street, or through private property acquired by the company, and to connect with the tracks of any other passenger railway company. The road must be operated electrically, or by any other power excepting steam. The company is to construct tubes or conduits for carrying city telegraph, telephone and fire alarm wires. Subsequently the company was further authorized to construct a loop, branch, or road beginning at the intersection of Broad and Market streets, on the south side of the City Hall, there connecting with its tracks, and thence extending south on Broad street to Walnut street to Fifth, thence to Arch, to Broad, to Filbert, and there connecting with its main tracks at Fifteenth and Market. This provided for two tracks on Market street east of Broad, and four tracks west of Broad in addition to the tracks already authorized. The alternate privilege was also granted of using Chestnut street instead of Walnut. The company is also privileged to bridge the Schuylkill so as to connect the subway tracks with the elevated tracks to be built to the west.
Routes of Different Companies. Similar ordinances were passed for the Ridge Avenue Elevated Passenger Railway Company to build a double-track elevated railway from Passyunk avenue along Ninth street to Vine, to Ridge avenue, to Main street, Manayunk.
The Frankford Elevated Passenger Railway Company is privileged to build a double-track road from South street along Delaware avenue to Vine, to Front, to Callowhill, to New Market, to Laurel, to Frankford avenue.
The Passyunk Avenue Elevated Passenger Railway is to extend from Delaware avenue along South street to Front, to Bainbridge, to Passyunk avenue, to Juniper, to Snyder avenue, to Schuylkill River.
The Germantown Avenue Elevated Passenger Railway is to extend from Front street along Germantown avenue to Germantown & Perkiomen turnpike, to the county line.
The Broad Street Subway Passenger Railway Company is authorized to construct an underground road from Government avenue under Broad street, around the Public Buildings, and continuing under Broad street to the county line.
Philadelphia Rapid Transit Company. On none of these lines was the requirement as to the beginning and completion of the work complied with; and the rights and privileges granted by the several ordinances would, therefore, have been forfeited, had it not been for the act above referred to providing for the extension of time of completion. All of the franchises have been acquired by the Philadelphia Rapid Transit Company, which operates all the surface lines in Philadelphia.
Description of Work. The plan proposed for the Market street line, now building, was an adaptation of the Boston method, and provided for both elevated and surface cars. The franchise for the line gave the right to build both an elevated road and a subway. There is a double-track elevated structure on Market street from the county line to the Schuylkill River, the surface tracks being underneath. A four-track bridge over the river carries both elevated and surface lines to the entrance of the subway at Twenty-third street. From this point to the Public Buildings is a four-track tunnel, the outside tracks for the surface cars, and the inside tracks for the elevated trains. The elevated tracks will continue around the City Hall and thence down Market street to the river front, where they will join an elevated structure on Delaware avenue from Arch to South streets. The surface car track will leave the other at the City Hall and pass south on Broad street in a single-track subway to Walnut street, to Fifth, to Arch, to Broad, to the City Hall, where it will unite with the westbound elevated track to the county line.
The tunnel is built with a concrete floor, steel-concrete side walls, and roof of I-beams with arches between, and rows of columns between the tracks. A considerable portion of this line has been finished. The bridge over the Schuylkill is practically complete. Work is now progressing on the elevated portion of the road west of the Schuylkill. An ordinance, passed in 1903, provided that each system of the railway must be finished before the streets are torn up for another system. The several sections must be completed in the following order: From Sixty-third and Market streets to Delaware avenue and South street, the system just mentioned, in three years from the passage of the ordinance.
Subway loop on Broad street and Walnut or Chestnut street, Fifth and Arch streets, one year additional.
Subway on Broad street, from Cayuga to Walnut or Chestnut, in two years additional.
Branches in West Philadelphia in two years additional, and the remainder within two years additional.