TKANSACTIOXS OF SECTION B. 117 



5. The Specific Heat of Gases at Constant Volume. 

 By Professor Bickkrton. 



It was shown that the specific heat of a rare moiiatomic gas 

 at constant volume must for many reasons he considered the 

 true specific heat of that atom, for in this state there is neither 

 internal nor external work. It was shown that by taking this 

 as the true specific heat most of the anomalies usvially 

 observed disappeared. That it also furnished a standard from 

 which to estimate the proportion of energy that went to 

 increase the velocity of the molecule, and that which was used 

 in overcoming external forces. Thus, for example, in heating 

 water, 40 per cent, (of energy) goes as heat, and 60 per cent, 

 in overcoming molecular attraction. 



6. 2Iolecular Attraction. 

 By Professor Bickertox. 



It was shown that this work, taken in terms of the expan- 

 sion, furnished a means of estimating the attraction of 

 molecules in terms of their diameter. It was shown that 

 the specific heat of constant pressure depends upon the 

 numbers of atoms of the molecule plus the difi^erence between 

 these two ratios in the case of a monatomic gas ; and this 

 fact must be taken into consideration in calculating the heat 

 developed by the compression of a gas. It was shown that 

 the attraction of moledules in terms of their diameters might 

 be estimated by comparing the complete isothermals of ii gas 

 with a rectangular hyperbola, — assuming the difference to be^ 

 due to molecular attraction helping the pressure by pulling the 

 molecules together. A third mode of estimating the attrac- 

 tion of molecules is to compress any gas until it ceases to 

 follow the gaseous laws, then allowing it to expand within a 

 calorimeter ; thus estimating the work in terms of the reduc- 

 tion of temperature, and from tliis deducing the moleculai* 

 attraction. 



7. Sotne possible Causes of the Lou- Tcniperatures of Partial 



Dissociation. 



By Professor Bickehton. 



It was shown that in the case of water the molecular attrac- 

 tion had an energy almost exactly equal to a temperature of 

 1,500'^' C, and that the attraction of molecules must curve 



