450 Prof. TyudalPs Contributions to Molecular Physics. 



Comparison of Tables IX. and X. — Absorption. 





Table IX. 



Table X. 



Bisulphide of carbon 



. 4-7 



4-7 



Chloroform . . . 



. 6-3 



6-5 



Iodide of methyle 



. 9-7 



9-6 



Iodide of ethyle . 



. 17-8 



17-7 



Benzole 



. 20-4 



20-6 



Amylene 



. 27-3 



275 



The agreement, it will be seen, is as perfect as could be 

 desired. 



Augmenting the opening through which the heat passed from 

 the source into the experimental tube, the total heat was increased, 

 and the experiments with a few of the vapours were repeated. 

 The total heat in the last case produced a deflection of 78°, which 

 is equal to 350 units ; the total heat now employed produced a 

 deflection of 83°, which is equal to 605 units. It is easy to see 

 that the experiments now to be recorded furnish a direct check 

 on the calibration of the galvanometer. As long as the quality 

 of the heat remains unchanged, the absorption ought to be the 

 same with a high total heat as with a low one. But if experi- 

 ment show that this is the case, it proves also that the calibra- 

 tion on which the calculation of the absorption depends, cannot 

 be in error. The following results were obtained on the 8th of 

 October : — 



Table X a. 



Amylene . . 

 Alcohol . . . 

 Formic ether . 

 Formic ether . 

 Sulphuric ether 

 Sulphuric ether 

 Acetic ether 

 Acetic ether 

 Total heat . . 



eflection. 



Absorption 



66-0 



28-7 



66-4 



29-2 



68-5 



32-5 



68-5 



32-5 



69-2 



33-6 



69-1 



334 



697 



34-5 



69-7 



34-5 



83-0 



100-0 



Placing the results beside those recorded in Table X., we have 

 the following comparison : — 



Comparison of Tables X. and X«. 



Amylene 

 Alcohol . . . 

 Formic ether . 

 Sulphuric ether 

 Acetic ether 



27-5 

 28-1 

 31-4 

 31-9 

 34-6 



28-7 

 292 

 32-5 

 33-5 

 34-5 



