418 



SCIENCE. 



[Vol. II., No. 34. 



ber can be utilized, and the remaining space 

 left clear. The mail matter can also be sorted 

 directlj- into bags, which are hung open 

 mouthed, at their four corners, on cast-iron 

 brackets, and these can also be folded out of the 

 ■way when not required. The letter-boxes are 

 provided with clips, into which labels can be 

 inserted, showing the destination of the letters 

 sorted into each particular box. 



The Pullman palace-car company- had a very 

 large exhibit of sleeping and dining cars, includ- 

 ing an emigrant sleeping-car, which will doubt- 

 less prove a great luxury* to settlers journeying 

 to the far west. The berths are arranged as in 

 an ordinarj- sleep- 

 ing-car, but consist 

 merely of slats of 

 ash, the bedding 

 and mattress (if 

 any) being provid- 

 ed by the emigrants 

 themselves. 



A new style of 

 sleeping - car, the 

 second of its kind 

 ever built, was 

 shown by the Paige 

 sleeping-car com- 

 pany. The top 

 berth does not fold 

 up against the roof 

 of the car, but is 

 a species of rectan- 

 gular hammock, 

 hung at the ends 

 from partitions be- 

 tween the sections. 

 These partitions, 

 in the day-time, 

 are lowered into a 

 space between the 

 backs of the seats. 

 The lower berth is not made on the seat, but 

 on a similar canvas hammock. 



A screw lever dump-car on Van Wormer's 

 patent is shown by the U. S. car company of 

 Boston, Mass. The centre support on the 

 trucks is a species of ball-and-socket joint, 

 combined with segments of two-toothed wheels, 

 — one segment being bolted to the top of the 

 truck-bolster, and the other to the under side of 

 the bottom framing of the car ; the effect being, 

 that, when the car is tipped, it rolls on the 

 trucks, the fulcrum on which it rolls being 

 brought directly under the centre of gravity of 

 the car and its load, which, of course, shifts 

 as the car is tipped. When the load is dumped, 

 the position of the centre of gravity tends to 



restore the car to its normal position : the 

 arrangement, therefore, assists the man in 

 charge both in dumping, and in restoring the 

 car to its running position. The rockers, with 

 the central ball and socket and segmental cogs 

 or teeth on either side, are shown in our illus- 

 tration. When the car is to be dumped, the 

 side-supports are withdrawn b}' means of levers 

 on the end-platforms, and the car is tipped to 

 either side by means of a worm actuated by a 

 hand- wheel. As the bottom of the car is solid, 

 it can be made stronger than a hopper-bottom 

 car, and can be used for freight, which requires 

 a flat floor, and cannot be loaded in a hopper- 

 bottom car. It is 

 stated that one man 

 can unload forty 

 thousand pounds of 

 coal, sanfl, ballast, 

 or iron ore, in two 

 minutes b}' means 

 of a dump-car, two 

 hours being re- 

 quired to shovel 

 out the same load. 

 The Suspension 

 car-truck manufac- 

 turing company of 

 New York exhib- 

 ited several trucks 

 made on their prin- 

 ciple, suited for 

 freight, passenger, 

 and horse cars, and 

 showed a model 

 truck which trav- 

 ersed an abnormal- 

 ly rough piece of 

 track with a very 

 smooth and eas}' 

 motion. The car 

 is connected to the 

 truck bj' means of links, which swing in a ver- 

 tical plane parallel with the track, instead of at 

 right angles to it, as in the swing-beam truck ; 

 while the axle-boxes are connected to the 

 trucks bj' means of links, which permit inde- 

 pendent side-motion to each axle. The nor- 

 mal position of all the links is vertical, and 

 they become inclined as the truck enters a 

 curve, and therefore tend to restore it to a 

 central position when the truck enters a piece 

 of straight track again. 



The principle (5f the truck is entirelj' novel, 

 and, though really simple, is best understood by 

 a few minutes' examination of a model. Two 

 brackets, resembling the letter A reversed, are 

 attached to the under side of the car. At the 



POSTAL-CAR RACKS. 



