MECHANICS AND USEFUL ARTS. 57 



Disk-springs of this kind have long been known ; they are peculiarly adapted 

 to car-springs, for they occupy no more space than the round India-rubber 

 springs now in common use. But the trouble with the old-fashioned disk- 

 spring is that, after being in use for a time, they split and flatten out, thus 

 losing their elasticity and becoming worthless. The improvement of Messrs. 

 Speed & Bailey consists in corrugating the disks, instead of having them 

 plain as heretofore. This invention adds new strength to the plates, and en- 

 tirely obviates the serious objections we have just named. 



Adams's Car Spring. In this new car-spring the inventor, Mr. Adams, of 

 New York, employs simply disks or circular pieces of cast-steel, between 

 which he lays circular plates of cast-iron. The latter are alternately convex 

 and concave ; that is, first thick at the edge, and next thickest in the middle, 

 the whole being confined within a case of cast-iron. Thus the weight of the 

 car is continually striving to bend each plate into a slightly dishing form, and 

 the elasticity and strength are so proportioned to the degree of curvature that 

 they may be compressed to a fair bearing before the plate of steel will be so 

 much distorted as to receive a permanent "set.'' In case, however, such an 

 event should occur, and that one or more of the plates in a series should be- 

 come permanently dished, the only result will be to carry the car somewhat 

 stiffer until, at a proper tune, the springs can be removed, when a few skillful 

 blows bring it into its original flat condition. 



One great point in this spring is the ease with which it may be lightened or 

 strengthened at pleasure, to adapt it to any kind of car or to any situation 

 desired. The same case, which is merely a cylinder open at the base, may be 

 made to contain a stiff or easy spring by increasing or diminishing the number 

 of steel disks between each alternate cast-iron plate. The springs now in 

 use are about 5 inches hi diameter outside the case, and 6 inches high when 

 extended. A motion of about li inches is provided for, which would make 

 the spring, when entirely compressed, about 4^- inches high. The plates of 

 steel are No. 20 by the wire-gauge, or considerably less than one sixteenth 

 inch thick, and it is preferred to place a few single, others double, treble, etc., 

 so that the spring will be equally elastic whatever the load in the car. The 

 spring can certainly be constructed very cheaply, as the castings require no 

 finishing, and the plates of steel are so light as to be of little moment so far 

 as expense is concerned. The only question* on which doubt may be felt is 

 the durability, as each depression of the center of the disk must cause a mo- 

 tion or rubbing of the surfaces at the edges ; a friction which, under so great 

 a pressure, may be supposed gradually to wear away both the metals. 



Miller's Steam, Car Brakt. In this invention by Mr. Henry Miller, of 

 Detroit, the cars are stopped by friction upon the wheels in the usual manner, 

 but the brakes are applied by the aid of steam from the boiler. Ordinary 

 hand-wheels are provided as usual at the ends of the cars, but except in case 

 of derangement or in switching the necessary pressure upon the brakes is ob- 

 tained in all cases ordinary as well as extraordinary from a piston confined 

 in a horizontal cylinder under the center of each floor. Every car is provided 

 with a pipe running lengthwise, and with a piece of strong flexible hose to 

 connect the same with that of the next one. This pipe supplies steam to one 



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