94 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



It is true that the curves cross in one or two instances, and are un- 

 evenly spaced at the high pressures, but the differences are very much 



TABLE XX. 

 Comparison of Thermal Expansion with Heat of Compression. 



less than one would expect from the differences in the initial direction 

 of the curves. The heat of compression is given hy Q = / ^ ( ^ ) dp. 



so that the relative initial values of 



St/j, 



, that is the initial slopes 



