ALLOYS 73 



outcome of the New Metallurgy and the flood of 

 light which it has thrown on the meaning and 

 nature of transformations and critical points. 



A similar sequence of scientific discovery and 

 subsequent and entirely unexpected practical ad- 

 vances flowing from them might be developed in 

 several other directions connected with the New 

 Metallurgy for instance in regard to special steels 

 whose peculiar electrical and magnetic properties 

 serve to lessen to a surprising extent the losses of 

 energy which occur in electrical transformers used 

 in connection with the transmission of power by 

 means of high-tension electric currents. One further 

 example only, however, can be mentioned, and 

 that has been chosen because it serves to illustrate 

 an entirely different direction in which the study 

 of the "constitutional diagram" of a system of 

 alloys may prove to be of surprisingly high practical 

 importance. A study of a number of these diagrams 

 at once brings out the fact that, broadly speaking, 

 there are two distinct types of alloy-systems. In 

 one of these, the two metals unite in much the 

 same way as salt unites with water when it is 

 dissolved in it a solution is formed when the two 

 metals are melted together and the two do not 

 separate when this solution freezes on cooling. 

 The resulting solid alloy has, in the ideal case, 

 a simple crystalline structure exactly like that of 

 a pure metal, but both metals are present in each 

 of the crystals. In the second type of alloys, 



