CAPACITY FOR HEAT OF METALS AT LOW TEMPERATURES. 
357 
7. Above liquid air temperatures .the three formulae above referred to are capable 
of approximately representing the results, but in some cases the discrepancies are 
considerable. 
At these higher temperatures the difference between C p and C v is considerable, and 
for some of the metals the increase in C t , is small. 
We take this opportunity of expressing our great indebtedness to Mr. D. A. Thomas 
for his gift of a complete liquid air plant. It was through his generosity that we 
were able to continue the investigation to low temperatures. 
Our thanks are due to the Court of the University of Wales for a contribution 
towards the expenses of this investigation, also to Mr. Edgar A. Griffiths, student 
in Engineering at this College, for constructing the special apparatus required and 
for his skilful management of the plant during the course of the work. 
