[Sidenote: _Emergency Signal System and Provision for Cutting Off Power from Contact Rail_]
In the booth of each ticket seller and at every manhole along the west side of the subway and its branches is placed a gla.s.s-covered box of the kind generally used in large American cities for fire alarm purposes. In case of accident in the subway which may render it desirable to cut off power from the contact rails, this result can be accomplished by breaking the gla.s.s front of the emergency box and pulling the hook provided. Special emergency circuits are so arranged that pulling the hook will instantly open all the circuit-breakers at adjacent sub-stations through which the contact rails in the section affected receive their supply of power. It will also instantly report the location of the trouble, annunciator gongs being located in the sub-stations from which power is supplied to the section, in the train dispatchers" offices and in the office of the General Superintendent, instantly intimating the number of the box which has been pulled.
Automatic recording devices in train dispatchers" offices and in the office of the General Superintendent also note the number of the box pulled.
The photograph on page 120 shows a typical fire alarm box.
CHAPTER VIII
ROLLING STOCK--CARS, TRUCKS, ETC.
The determination of the builders of the road to improve upon the best devices known in electrical railroading and to provide an equipment unequaled on any interurban line is nowhere better ill.u.s.trated than in the careful study given to the types of cars and trucks used on other lines before a selection was made of those to be employed on the subway.
All of the existing rapid transit railways in this country, and many of those abroad, were visited and the different patterns of cars in use were considered in this investigation, which included a study of the relative advantages of long and short cars, single and multiple side entrance cars and end entrance cars, and all of the other varieties which have been adopted for rapid transit service abroad and at home.
The service requirement of the New York subway introduces a number of unprecedented conditions, and required a complete redesign of all the existing models. The general considerations to be met included the following:
High schedule speeds with frequent stops.
Maximum carrying capacity for the subway, especially at times of rush hours, morning and evening.
Maximum strength combined with smallest permissible weight.
Adoption of all precautions calculated to reduce possibility of damage from either the electric circuit or from collisions.
The clearance and length of the local station platforms limited the length of trains, and tunnel clearances the length and width and height of the cars.
The speeds called for by the contract with the city introduced motive power requirements which were unprecedented in any existing railway service, either steam or electric, and demanded a minimum weight consistent with safety. As an example, it may be stated that an express train of eight cars in the subway to conform to the schedule speed adopted will require a nominal power of motors on the train of 2,000 horse power, with an average accelerating current at 600 volts in starting from a station stop of 325 amperes. This rate of energy absorption which corresponds to 2,500 horse power is not far from double that taken by the heaviest trains on trunk line railroads when starting from stations at the maximum rate of acceleration possible with the most powerful modern steam locomotives.
Such exacting schedule conditions as those mentioned necessitated the design of cars, trucks, etc., of equivalent strength to that found in steam railroad car and locomotive construction, so that while it was essential to keep down the weight of the train and individual cars to a minimum, owing to the frequent stops, it was equally as essential to provide the strongest and most substantial type of car construction throughout.
Owing to these two essentials which were embodied in their construction it can safely be a.s.serted that the cars used in the subway represent the acme of car building art as it exists to-day, and that all available appliances for securing strength and durability in the cars and immunity from accidents have been introduced.
After having ascertained the general type of cars which would be best adapted to the subway service, and before placing the order for car equipments, it was decided to build sample cars embodying the approved principles of design. From these the management believed that the details of construction could be more perfectly determined than in any other way. Consequently, in the early part of 1902, two sample cars were built and equipped with a variety of appliances and furnishings so that the final type could be intelligently selected. From the tests conducted on these cars the adopted type of car which is described in detail below was evolved.
After the design had been worked out a great deal of difficulty was encountered in securing satisfactory contracts for proper deliveries, on account of the congested condition of the car building works in the country. Contracts were finally closed, however, in December, 1902, for 500 cars, and orders were distributed between four car-building firms. Of these cars, some 200, as fast as delivered, were placed in operation on the Second Avenue line of the Elevated Railway, in order that they might be thoroughly tested during the winter of 1903-4.
[Ill.u.s.tration: END VIEW OF STEEL Pa.s.sENGER CAR]
In view of the peculiar traffic conditions existing in New York City and the restricted siding and yard room available in the subway, it was decided that one standard type of car for all cla.s.ses of service would introduce the most flexible operating conditions, and for this reason would best suit the public demands at different seasons of the year and hours of the day. In order further to provide cars, each of which would be as safe as the others, it was essential that there should be no difference in constructional strength between the motor cars and the trail cars. All cars were therefore made of one type and can be used interchangeably for either motor or trail-car service.
The motor cars carry both motors on the same truck; that is, they have a motor truck at one end carrying two motors, one geared to each axle; the truck at the other end of the car is a "trailer" and carries no motive power.
[Ill.u.s.tration: SIDE VIEW OF STEEL Pa.s.sENGER CAR]
Some leading distinctive features of the cars may be enumerated as follows:
(1.) The length is 51 feet and provides seating capacity for 52 pa.s.sengers. This length is about 4 feet more than those of the existing Manhattan Elevated Railroad cars.
(2.) The enclosed vestibule platforms with sliding doors instead of the usual gates. The enclosed platforms will contribute greatly to the comfort and safety of pa.s.sengers under subway conditions.
(3.) The anti-telescoping car bulkheads and platform posts.
This construction is similar to that in use on Pullman cars, and has been demonstrated in steam railroad service to be an important safety appliance.
(4.) The steel underframing of the car, which provides a rigid and durable bed structure for transmitting the heavy motive power stresses.
(5.) The numerous protective devices against defects in the electrical apparatus.
(6.) Window arrangement, permitting circulation without draughts.
(7.) Emergency brake valve on truck operated by track trip.
(8.) Emergency brake valve in connection with master-controller.
The table on page 133 shows the main dimensions of the car, and also the corresponding dimensions of the standard car in use on the Manhattan Elevated Railway.
The general arrangement of the floor framing is well shown in the photograph on page 132. The side sills are of 6-inch channels, which are reinforced inside and out by white oak timbers. The center sills are 5-inch I-beams, faced on both sides with Southern pine. The end sills are also of steel shapes, securely attached to the side sills by steel castings and forgings. The car body end-sill channel is faced with a white-oak filler, mortised to receive the car body end-posts and braced at each end by gusset plates. The body bolster is made up of two rolled steel plates bolted together at their ends and supported by a steel draw casting, the ends of which form a support for the center sills. The cross-bridging and needle-beams of 5-inch I-beams are unusually substantial. The flooring inside the car is double and of maple, with asbestos fire-felt between the layers, and is protected below by steel plates and "transite" (asbestos board).
The side framing of the car is of white ash, doubly braced and heavily trussed. There are seven composite wrought-iron carlines forged in shape for the roof, each sandwiched between two white ash carlines, and with white ash intermediate carlines. The platform posts are of compound construction with anti-telescoping posts of steel bar sandwiched between white ash posts at corners and centers of vestibuled platforms. These posts are securely bolted to the steel longitudinal sills, the steel anti-telescoping plate below the floor, and to the hood of the bow which serves to reinforce it. This bow is a heavy steel angle in one piece, reaching from plate to plate and extending back into the car 6 feet on each side. By this construction it is believed that the car framing is practically indestructible. In case of accident, if one platform should ride over another, eight square inches of metal would have to be sheared off the posts before the main body of the car would be reached, which would afford an effective means of protection.
[Ill.u.s.tration: EXTERIOR VIEW--STEEL CAR FRAMING]
The floor is completely covered on the underside with 1/4-inch asbestos transite board, while all parts of the car framing, flooring, and sheathing are covered with fire-proofing compound. In addition, all s.p.a.ces above the motor truck in the floor framing, between sills and bridging, are protected by plates of No. 8 steel and 1/4-inch roll fire-felt extending from the platform end sill to the bolster.
[Sidenote: _Car Wiring_]
The precautions to secure safety from fire consists generally in the perfected arrangement and installation of the electrical apparatus and the wiring. For the lighting circuits a flexible steel conduit is used, and a special junction box. On the side and upper roofs, over these conduits for the lighting circuits, a strip of sheet iron is securely nailed to the roof boards before the canvas is applied. The wires under the floor are carried in ducts moulded into suitable forms of asbestos compound. Special precautions have been taken with the insulation of the wires, the specifications calling for, first, a layer of paper, next, a layer of rubber, and then a layer of cotton saturated with a weather-proof compound, and outside of this a layer of asbestos. The hangers supporting the rheostats under the car body are insulated with wooden blocks, treated by a special process, being dried out in an oven and then soaked in an insulating compound, and covered with 1/4-inch "transite" board. The rheostat boxes themselves are also insulated from the angle iron supporting them. Where the wires pa.s.s through the flooring they are hermetically sealed to prevent the admission of dust and dirt.
At the forward end of what is known as the No. 1 end of the car all the wires are carried to a slate switchboard in the motorman"s cab.
This board is 44 x 27 inches, and is mounted directly back of the motorman. The window s.p.a.ce occupied by this board is ceiled up and the s.p.a.ce back of the panels is boxed in and provided with a door of steel plate, forming a box, the cover, top, bottom, and sides of which are lined with electrobestos 1/2-inch thick. All of the switches and fuses, except the main trolley fuse and bus-line fuse, which are encased and placed under the car, are carried on this switchboard.
Where the wires are carried through the floor or any part.i.tion, a steel chute, lined with electrobestos, is used to protect the wires against mechanical injury. It will be noted from the above that no power wiring, switches, or fuses are placed in the car itself, all such devices being outside in a special steel insulated compartment.
A novel feature in the construction of these cars is the motorman"s compartment and vestibule, which differs essentially from that used heretofore, and the patents are owned by the Interborough Company. The cab is located on the platform, so that no s.p.a.ce within the car is required; at the same time the entire platform s.p.a.ce is available for ingress and egress except that on the front platform of the first car, on which the pa.s.sengers would not be allowed in any case. The side of the cab is formed by a door which can be placed in three positions.
When in its mid-position it encloses a part of the platform, so as to furnish a cab for the motorman, but when swung parallel to the end sills it encloses the end of the platform, and this would be its position on the rear platform of the rear car. The third position is when it is swung around to an arc of 180 degrees, when it can be locked in position against the corner vestibule post enclosing the master controller. This would be its position on all platforms except on the front of the front car or the rear of the rear car of the train.
The platforms themselves are not equipped with side gates, but with doors arranged to slide into pockets in the side framing, thereby giving up the entire platform to the pa.s.sengers. These doors are closed by an overhead lever system. The sliding door on the front platform of the first car may be partly opened and secured in this position by a bar, and thus serve as an arm-rest for the motorman. The doors close against an air-cushion stop, making it impossible to clutch the clothing or limbs of pa.s.sengers in closing.
[Ill.u.s.tration: INTERIOR VIEW--SKELETON FRAMING OF STEEL CAR]
Pantagraph safety gates for coupling between cars are provided. They are constructed so as to adjust themselves to suit the various positions of adjoining cars while pa.s.sing in, around, and out of curves of 90 feet radius.
On the door leading from the vestibule to the body of the car is a curtain that can be automatically raised and lowered as the door is opened or closed to shut the light away from the motorman. Another attachment is the peculiar handle on the sliding door. This door is made to latch so that it cannot slide open with the swaying of the car, but the handle is so constructed that when pressure is applied upon it to open the door, the same movement will unlatch it.
Entering the car, the observer is at once impressed by the amount of room available for pa.s.sengers. The seating arrangements are similar to the elevated cars, but the subway coaches are longer and wider than the Manhattan, and there are two additional seats on each end. The seats are all finished in rattan. Stationary crosswise seats are provided after the Manhattan pattern, at the center of the car. The longitudinal seats are 17-3/4 inches deep. The s.p.a.ce between the longitudinal seats is 4 feet 5 inches.
The windows have two sashes, the lower one being stationary, while the upper one is a drop sash. This arrangement reverses the ordinary practice, and is desirable in subway operation and to insure safety and comfort to the pa.s.sengers. The side windows in the body of the car, also the end windows and end doors, are provided with roll shades with pinch-handle fixtures.