152 TRANSACTIONS OF THE [fEB. 1, 



The weight of rails is increasing. The first steel rails, in 1863, 

 weighed 5G lbs. per yard. The weight soon increased to GO lbs., 

 then to 05 lbs. and 67 lbs. about 1870. Many of the New Eng- 

 land roads are now using 72 lb. rails. The section here exhibited 

 weighs 80 lbs. per yard, and is one pattern used by the N. Y. C. & 

 H. K. E. II. In England the rails weigh from 70 to 90 lbs. Large 

 quantities of 80 lbs. are used. The double headed rail is very 

 common, and it is laid in cast-iron chairs, one upon eacli tie, the 

 latter being about three feet apart from centre to centre. Some 

 roads use flat-bottom rails similar to those employed in this 

 country. 



The weight of locomotives is increasing. Many for passenger 

 service now weigh forty-five tons exclusive of the tender. 



The adhesion of the locomotive is, on dry rails, over one-third 

 the Aveight upon the drivers, but it decreases to about one-fourth 

 or one-fifth on a slimy rail. A wet rail washed clean decreases 

 the adhesion very little. 



The dynamometrical curve indicating the power used in start- 

 ing and running a train, would at first, in starting, be the full 

 traction the locomotive could exert — from about 12,000 lbs. to 

 10,000 lbs.; the latter being for the largest passenger locomotives. 

 The curve falls rapidly at first as the train gains motion, then 

 more slowly; and finally becomes quite uniform in height for a 

 definite speed and level track. For a train of ten cars at a speed 

 of fifty miles per hour the dynamometer shows a tension on the 

 draw-bar of 3,000 to 3,200 pounds. To attain this speed re- 

 quires usually a run of four or five miles. While the tension 

 upon the draw-bar is not so great for long trains as many persons 

 suppose, the consumption of power is, liowever, far greater. A 

 train of the size above noted would require from 500 to GOO horse- 

 jiower, and some of the faster trains consume 800 to 1,000 horse- 

 power. 



Very few iron ties have been used in this country, and the 

 experience is limited. In Germany they have been extensively 

 used; also in India, and to some extent in England. 



Paper wheels are in extensive use under passenger cars. In 

 regard to economy in their use there is some difference of 

 opinion; but their greater safety is unquestioned. 



The President referred to the rail invented by Mr. Booth, 

 which had been exhil)ited many years ago to tiiis Society. Of 

 this rail the base, web, and a small head were of iron. Over the 

 small head a cap of crucible steel was rolled, which gave a hard 

 wearing surface combined with a tough iron base. Many thous- 

 and tons of these rails were used. But about this time Bessemer 

 steel was introduced and superseded all other steel rails. In. 

 consequence, Mr. Booth realized very little from his invention. 



