1 68 ELEMENTS OF APPLIED MICROSCOPY. 



All these factors are of great importance in determining 

 the hardness of steel; it is therefore natural that the 

 microscope should have become indispensable in the 

 laboratory of the iron and steel expert. Its practical 

 application to the study of other alloys promises exten- 

 sive development in the future. 



REFERENCES. 



Clark, C. H. Practical Methods in Microscopy. Boston, 



1894. 

 LuQUER, L. M. Minerals in Rock Sections. New York, 1898. 

 Zerkel, F. Lehrbuch der Petrographie. Leipsic, 1893. 

 RosENBUCH, H. Iddings, J. P. (translator). Microscopical 



Physiography of the Rock -making Minerals. New York, 



1893. 

 HiORNS, A. H. Metallography. London, 1902. 

 Sauveur, a. The Constitution of Steel considered as an Alloy 



of Iron and Carbon. Technology Quarterly, XI, 1898, 78. 



