76 JOURNAL OF THE [July, 



wearing rail of dense metal in the head, to start with a good 

 chemical composition as a basis; the carbon .50 or more; to make 

 a small texture in the ingot; avoid long or over-heating; have a 

 section of rail with a thin head to be well worked, a thick base 

 and heavy web to equalize the heat in the section to give tough- 

 ness to the metal and not brittleness. 



The foliated structure we see between the crystals, and a similar 

 structure which has built them up, become reduced to more deli- 

 cate laminae as the imperfect crystals are broken up by mechan- 

 ical work. The soft steels do not have sufficient cohesion to 

 prevent flow under the loads of the present day. To give such 

 steel strength mechanical work must be done upon the plates, or 

 some elements added which will modify the structure or increase 

 the cohesion of the laminae. 



The first steel rails of only .25 to .4 of carbon, with thin heads, 

 thick bases and webs, made with 23 passes in the rail train, had 

 line structure in the heads and were excellent rails, though in a 

 few years the sections were not stiff enough for the increasing 

 trafific. Noticing that the rate of wear was very slow in the head, 

 the conclusion was soon reached that massive heads, thin bases 

 and webs would give the longest service. This soon became the 

 style of all new sections. The structure, from a fine one in the 

 heads of old rails, became coarse in the new and wore out at 

 much faster rate. Then a hasty conclusion was reached, from 

 an insufficient investigation, that a small amount of carbon in the 

 rails, low manganese, silicon and phosphorus not exceeding .10, 

 would make better wearing rails than higher grades of steel. We 

 have had an era of massive heads, coarse structure, and soft rails 

 which have not given, long service. The metal not only rapidly 

 abrades, but flows, and is forced from the rails. This is illustrated 

 by specimens Nos. 20, 2 r, and 22. Slower-wearing rails are 

 shown in specimens Nos- 23 and 24, the latter having had double 

 the number of years' service of Nos. 20, 21, and 22. 



Specimens Nos. 25, 26, 27, 28, and 29 are some of the sections 

 I have introduced with thinner and broader heads to insure fine 

 structure, as the rails are made by the present rapid methods. 



The chemical composition has also been changed to one much 

 harder than formerly, the product in these sections being tough 

 and not brittle. In .60 carbon rails an elongation of 10 to 18 per 



