AMERICAN INSTITUTE. 549 



lience I hold that as we increase the mechanical perfection of 

 railroad science we shall in so far jnc:e;ise its safety and profit. 



Ail railroad casualties occiu- d.stinctJy to or in consequence of 

 trains in motion, and in proportion as the momentum is great or 

 small is the damage that naturally takes place. The weight of 

 a first class locomotive and tender is about 35 tons; the weight of 

 bjg^age and passenger cars is about 12 tons each, so that the 

 weight of a train of seven cars, engine and tend r is in round 

 numbers, 119 tons. Such a body of matter moving at the rate 

 of 3U miles per hour exerts an impulsive force of t'lree thousand 

 tons, that is, presupposing that the entire troia was one solid mass, 

 perfectly unyielding in all i:s parts. But it is well known that 

 there is considerable elastici'y between the cars, trucks, &:c. Sec, 

 so that in all probability the actual force of a train, of weight 

 an 1 speed as above, at the moment of striking does not exceed 

 seven hundred tons. How shall this terriiic power be averted or 

 checked in times of sudden or uaexpecled danger. For all ordi- 

 nary purposes when no danger is near, w^e are w^ell enough pro- 

 vided already. This question naturally brings us directly to the 

 subject matter of this paper, viz : railroad car brakes. My 

 earliest recollection of railroad car brakes were those used on the 

 Palerson and Hudson River Railroad, about the year 1833 and 4. 

 The cars that w^ere at that time used were similar to those now 

 in use on most of the European railroads, viz : single truck cars 

 with three divisions in each calcula'ed for twenty-four passengers; 

 on the top at each end was a seat for a brakeman, and one was 

 provided for each car. My impressions are that no whistle was 

 used on the engine, or signal of any kind; the brakemen were 

 constan'ly on the lookout, and applied the brakes where in their 

 own judgment they were required. The plan of brakes was as fol- 

 lows : between the wheels on each side were hung blocks of wood 

 cut out to fit the surf ice or tread of the wheel, to each block was 

 attached a rod pointing downward about thirry degrees from a 

 horizontal line, these rods were connec^^ed again to a vertical 

 rod, which being pulled upward spread the blocks apart pressing 

 tliem against the wheels. Cross ways the car was a shaft with an 

 arm at each end attaching to the vertical rods between the brake 

 block-', there was also a vertical arm projecting from the centre 

 of the sliafr to which was attached a horizontal connecting rod, 

 connecting wi;h a verlical rod npon which the brakeman pressed 

 his fiot when he applied the brake. This plan was in use, I 

 thinkj as long as the single truck cars were in this country. 



