148 TKANSACTIONS OF THE [fEB. 1^ 



through the molten metfil, thus producing intense combustion, 

 burning out the excess of carbon. On a small scale, some steel 

 Avas iiroduced, but commercially it was not a success, and the iron 

 masters denounced him. Bessemer, with that true inventive 

 genius which is never bullied by obstacles as long as there is life, 

 burned out all of the carbon, or decarbonized the iron, then 

 added spiegeleisen to return the percentage of carbon and man- 

 ganese required, and it became a great commercial success. The 

 molecular change produced in the metal so improved it that it 

 has permitted the extension of the railway system into new sec- 

 tions of the country, thus building them up instead of the coun- 

 try building up the railroads; and it has enabled lower rates of 

 freight to be made than was then expected. 



Tiie prejudice against steel rails was strong, and this country 

 is indebted to the late Alexander Holley for introducing and so im- 

 proving the Bessemer plant, that to-day a ton of this steel can 

 be made for less cost than a ton of wrought iron. To cheapen 

 it so much has been at some expense of quality, and under heavy 

 traffic the rails are now wearing more rapidly than those first 

 used. The steelmakers are, however, not wholly responsible for 

 this. 



The paramount question of all roads is safety, and the breaking 

 of a few rails led to the use of softer steel. It may seem a singu- 

 lar fact that more steel rails break the first year after being 

 laid than afterwards. The causes of this are generally found to 

 be due to injuries in straightening at the mills and careless 

 handling before being laid — faults that should be remedied irre- 

 spective of the quality of the steel. 



The results of some investigations have been interpreted as show- 

 ing that soft rails wear the best. I have not found this to be the 

 case, considering the physical properties. The chemical compo- 

 sition alone does not indicate the wearing properties. 



Eail steel is not homogeneous or amorphous, but consists of 

 aggregations oC molecules of metal, having a delicate layer (pos- 

 sibly carbide of iron) joining one aggregation to another, and, 

 as far as I have examined, the softer or coarser the steel the larg- 

 er the aggregations; and in rolling tliey become elongated. In 

 steel tires of driving and car wheels, some of these become de- 

 tached, producing aseriesof irregularities as shown in our photo- 

 graphs. Soft steel rails wear in a similar manner, to some 

 extent. 



From the first practical operations of steam locomotion in the 

 United States — about 1830 — our railways have developed in 

 extent and capacity, exceeding all other countries. 130,000 

 miles of main line are reported, and 26,000 miles more as addi- 

 tional track and sidings. Locomotives to operate them number 



