74 JOURNAL OF THE [July» 



tals formed, producing a structure which was not strong under 

 shock, fracture taking place between instead of through the crys- 

 tals. So well-defined structure I have only found in a rail head 

 once and that was the rejected rail from which specimen No. 2, 

 described in my previous paper, was taken. It is a form of struc- 

 ture I do not wish to find either in the ingot or in the rail. Seve- 

 ral attempts were made to break up the structure as formed in 

 the rail head, and while a considerable modification was made, 

 removing some of the brittleness of the metal, the structure was 

 not completely effaced. It seems much safer to prevent its for- 

 mation than to try and break it up afterwards. 



In specimen No. 9, of the same ingot, in one of the gas cavities 

 you will see the well-developed pine-tree crystals. The same 

 form of crystals also studded the pipe which formed in the upper 

 part of the ingot. 



In the practice of making rails, the ingots as 5oon as stripped, 

 8 to 12 minutes after casting, are charged into a reheating fur- 

 nace or soaking pit to equalize the temperature before blooming. 

 In the latter operation many of the gas cavities and portions of 

 the pipe become closed. The portion of the bloom in which the 

 pipe is not closed is cut out. It is often the case that the inte- 

 rior of the ingot is not fully solidified upon reaching the blooming 

 train, more or less segregation having taken place, producing an 

 ent rely different structure in the centre of the rail. This is not 

 desirable, as the rails are liable to be brittle. Specimens Nos. 1 1, 

 12, and 13 are pieces from such rails which failed to stand a drop 

 test of 2,000 pounds falling 20 feet, the rail butt resting upon steel 

 supports of 4 feet span. Before placing the rail upon the sup- 

 ports the base is stamped into inch sections, so the percentage of 

 elongation can be ascertained ; any rail failing to give five per 

 cent elongation, the entire rails of the heat are rejected. The 

 carbon and manganese are usually much greater in the central 

 portions of such ingots. In specimen No. 1 1 the average carbon 

 of the heat was .48 and the manganese .90. In the centre of the 

 ingot the carbon was .60 and the manganese 148 per cent. In 

 specimen No. 12 segregation occurred in the metal forming the 

 centre of the head of the rail, the surrounding metal also being 

 weak and easily fractured. 



Specimen No. 14 shows a piece of tough rail which was placed 



