Meigs Elevated Railway

Meigs Elevated Railway
Overview
Locale East Cambridge, Massachusetts
Transit type straddle-beam monorail
Number of lines 1
Operation
Operator(s) Joe V. Meigs

The Meigs Elevated Railway was an experimental steam-powered monorail invented by Josiah V. Meigs (also known as Joe Vincent Meigs)[1] of Lowell, Massachusetts. He wrote an extensive explanation of how the railway worked, complete with diagrams and statistics, which was published in 1887.[2] The weight of the train was carried on a 22 inch gauge track. The train was balanced by an additional set of horizontal wheels which operated against a second set of rails 42 inches above the load carrying rails. A fire, supposedly of an incendiary nature, broke out on the night of Feb. 4, 1887, and destroyed Meigs's car sheds along with the experimental coach and tender and severely damaged the locomotive.

History

Joe Meigs built his elevated railway to demonstrate the benefits and capabilities of a monorail under widely varying circumstances. A 227-foot demonstration line was built in 1886 in East Cambridge, Massachusetts on land abutting Bridge Street, now Monsignor O'Brien Highway. Never expanded, it ran until 1894.[1]

A section in the act of the Massachusetts legislature authorizing the incorporation of the Meigs Elevated Railway Company states that "no location for tracks shall be petitioned for in the city of Boston until at least one mile of the road has been built and operated, nor until the safety and strength of the structure and the rolling stock and motive power shall have been examined and approved by the board of railroad commissioners or by a competent engineer to be appointed by them." The company built tracks of several kinds:

Top view: Fig. 2 is a plan view of a train on a sharp curve, Fig. 3 is an end view of the track and the engine, Fig. 4 is a section through tender and track, and Fig. 5 is a section through the car

The trial road, beginning at the shops of the company on Bridge Street (now Gore and Monsignor O'Brien Highway), East Cambridge, had one curve of 50 feet radius, 165 feet long, on a grade of 120 feet, and on level and curves has grades of 240 feet, 300 feet, and 345 feet. Everything has worked in the most satisfactory manner, the train rounding the exceedingly sharp curves easily, and mounting the steep grades without trouble. The posts for an iron way were made up of two channel bars united by two plates, thereby forming a box-like structure whose cross section may be varied as demanded by location. The posts were placed upon foundations, the plans of which varied to suit the character of the material that may be encountered.[3]

The way upon which the train ran consisted of a single iron girder 4 feet in depth for each span, placed over the center line of the posts. The girder carried an upper track beam and a lower track beam, upon the sides of each of which the rails, four in number, were placed. The two bearing rails, which carried the load of the train, consisted of angle irons placed upon the outer upper edge of wooden stringers upon the lower track beam. These stringers were placed in the exterior recesses formed by two channel bars properly secured to the sides of the posts. These rails were fastened to each other, to the stringers, and to the track beam by bolts passing clear through. Two vertically placed rails for the balancing or friction wheels were carried by the upper track beam. The distance from out to out between the lower rails was 22½ inches, this being sufficient to insure the necessary transverse stiffness. This was the gauge of the road. The distance between the upper rails was 17½ inches. It was expected to adopt the common form of rail, beveling the edges of the lower stringers and placing the rail at an angle of about 45 degrees. The rails were in the form of a right angle, and the treads of the wheels were made with a corresponding right angle groove. The usual length of post, 24 feet, would give a clear headway of 14 feet, 4 feet being taken up by the truss and 6 feet forming the foundation.[3]

The switch was formed of a single swinging section turning upon a hinge of great strength attached to one of the posts. A movement of four or five feet by the free end of the switch was enough to permit the cars and trucks on one track to clear the end of the other track. The free end travels upon a carriage provided with rollers moving upon a supporting rail. Suitable mechanism was provided for operating the switch and locking it in place.

The truck was a development of the conditions controlling the adoption of the permanent way. It consisted of a horizontal rectangular wrought iron frame, stiffened by cast iron pieces and provided with stiff pedestals bolted to its under side, in which was a fixed short axle for the wheels. Each truck had four wheels set at an angle of about 45 degrees, the axles being properly inclined. Between the supporting wheels were two horizontal wheels, one on each side of the upper girder, upon vertical axles attached to the frame. These wheels bear upon the rails of the upper truck beam, and were kept in yielding contact with the rails by springs outside the boxes, and served as balancing wheels to take the side oscillations of the cars. They were formed with flanges that passed under the lower edges of the rails, thus tying the truck to the rails, so that no lifting or jumping could take place, and there was no possibility of the trucks running off the track. The wheels were 42 inches in diameter, had a tread of 3½ inches, and rotated independently of each other. In case any or all of the wheels should break, provision was made to prevent the cars from overturning or leaving the track, by means of a strong shoe, which would slide upon but could not leave the way. On top of the truck frame was a movable iron frame carrying four posts containing heavy spiral springs. These posts interlock with similar spring sockets bolted to the framing of the floor of the car, which was directly above the truck and within 18 inches of the top of the girder. The truck was guided in turning by a center pin, and was securely tied to the car body, as the horizontal flanges of its frame castings overlap the rim of the upper turntable. In passing curves and switches, the trucks turned upon the balancing wheels, placed centrally between the supporting wheels, which were 4 feet apart.[3]

It has been found that, by reason of the independent motion of all the truck wheels, curves were followed so closely that practically the increase of friction of the cars upon curves even as small as 50 feet radius was too slight to be noticed or measured by weighing in a model one-eighth full size. This construction of the trucks also admitted of a car 50 feet long turning from a street only 28 feet wide into another of the same width.

Internal view

The cars possessed many novel features, both outside and inside. The circular section and rounded ends admitted of the strongest possible construction without an overweight of material. The floor consists of a platform made of 5 inch channel beams, and was 7½ feet wide by 51 feet 2 inches long. The framing of the body was of light T iron ribs, bent in a circle, filled in by panels covered with rich upholstering, which covers all the interior; the exterior was sheathed with paper and copper. The cylindrical portion was 10 feet 8½ inches in diameter. While adding to the strength, this form was expected to diminish the wind resistance fully one-third. The interior of the car was light, roomy, and pleasing to the eye. The seats were upholstered like the rest of the car, and comfort and luxury have been carefully studied in every detail. At each window was a specially designed device for securing ventilation without the annoyance caused by dust. There was an entire absence of sharp corners, so that, in case of a serious accident, the liability of the passenger being greatly injured was largely avoided.[3]

The locomotive consisted of a platform car supported upon a truck at either end and housed like the passenger car. The floor was 7½ feet wide by 29¼ feet in extreme length; the tender was 24⅔ feet long, had a tank for the water and a bin for the coal, besides additional room for other purposes. Upon the floor of the engine were, in effect, two complete stationary engines, each connected with a single driving wheel. The boiler was of the locomotive type, was 60 inch in diameter, 15 feet in length, and was placed over the engines, its center line being 61 inch above the floor. There were 200 tubes, 2 inch in diameter and 7 feet long; the grate is 4½ feet square. The crown sheet was arched in shape, and was inclined downward at the back end to allow of climbing and descending grades equal to 800 feet to the mile without exposing any uncovered part to the fire. The cylinders were 12 by 22 inch, and their center lines were placed 18 inch above the floor and 61 inch apart. The piston rods connected with independent crossheads gliding upon steel girders supported at their ends by standards bolted to the floor beams.[3]

The driving wheels were 44.6 inch in diameter, flanged upon their lower edge like the balance wheels of the trucks, and were mounted upon steel axles 6 inch in diameter, which extend through a sliding box containing the journals. The boxes slid in cast iron ways placed at right angle to the line of the engine, and each axle had a crank keyed upon its upper end. The well known slotted yoke connection was used. The slide valves were of the usual locomotive form. The links were placed in a horizontal instead of a vertical position, and were operated by two bell cranks. The throttle valve, link rod, brake, and coupling rods, and the connection between the driving boxes for producing pressure against the rails, were operated by hydraulic power, although hand levers were also provided.[3]

Adhesion of the driving wheels to the rails was obtained by means of a cylinder and piston secured to the sliding boxes. The engineer was on an elevated platform in the front part of the engine, the fireman being at the rear end. The former had an unobstructed view through the windows of the monitor roof, and before him were five hydraulic cocks, which control the throttle, links, sliding boxes of the driving wheels, the brake, and the coupling rods of the entire train, while just above were steam and hydraulic pressure gauges and indicators, whistle and bell ropes, etc. With an engine thus furnished with provisions for gripping the rails, steep grades became of minor importance, as the steepest possible could be ascended if the requisite power was provided.[3]

One turn of the cock controlling the couplings divided the train into segments of separate cars, each of which had a brake which acted automatically upon detachment from the train. This partially destroyed the momentum of the whole, and a collision could only take place by a succession of comparatively light blows from the engine and slowing sections of the train, instead of by a single blow with the momentum of the whole train. The brakes were operated upon the balancing wheels of the trucks, but they mayed also be fitted upon the supporting wheels. The action of the brakes could be well illustrated by rails between the rolls of a rolling mill, except that the action was reversed. It was apparent that no slipping of the wheels can take place, no matter what pressure may be brought to bear upon them.[3]

This system was as applicable for surface as for elevated railroads. It was more cheaply to build than the ordinary road, as the construction of the rolling stock allowed the contour of the ground to be more closely followed. As an elevated road in cities, the permanent structure presented far less obstruction to light and air than the usual form. The center of gravity of the cars and engine was brought as low as possible, thereby lessening the effect of leverage caused by wind pressure. The smooth, even surface of the exterior of the entire train served to decrease the resistance to the wind, and permitted a high rate of speed.[3]

Gallery

External links

References

  1. 1 2 Robert Campbell and Peter Vanderwarker: "MEIGS ELEVATED RAILWAY". Boston Globe, February 23, 1992.
  2. ↑ Meigs, Joe V., "The Meigs Elevated Railway System: The Reasons For Its Departures From The Ordinary System," 1887 (Boston: Charles H. Whiting).
  3. 1 2 3 4 5 6 7 8 9 10 "The Meigs Elevated Railway". Scientific American. 1886-07-10. Retrieved 2015-07-03. This article incorporates text from this source, which is in the public domain.
Wikimedia Commons has media related to Meigs Elevated Railway.

Coordinates: 42°22′05″N 71°04′15″W / 42.3680°N 71.0708°W / 42.3680; -71.0708

This article is issued from Wikipedia - version of the Sunday, April 17, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.