CHAPTER IV 



FUSION AND SOLIDIFICATION 



For more is not reserved 



To man, with soul just nerved 

 To act to-morrow what he learns to-day : 



Here work enough to watch 



The Master work and catch 

 Hints of the proper craft, tricks of the tool's true play. 



— Browning, Rabbi Ben Ezra. 



In the previous chapter we have discussed chiefly 

 the methods employed to bring about a change 

 of state, especially that change of state which 

 consists in passing from the gaseous to the liquid 

 or solid condition in the case of those substances 

 which at ordinary temperatures and pressures 

 exist as gases. The methods employed and the 

 principles underlying them were the points of 

 interest, and the whole subject belonged to that 

 branch of physical science which consists in recog- 

 nising and overcoming difficulties of manipula- 

 tion, and, as it were, of asserting by force the 

 superiority of mind over matter. 



But, throughout the investigations to be 

 pursued in the present chapter, our attitude is 

 altered. There is no need for such attempted 

 assertion of supremacy. The changes of state 

 to be examined are already under our control, 

 and we are able to investigate further details, and 

 probe more deeply into the intimate nature of 

 the processes involved. We patiently seek to 



68 



