M. E. Wiedemann on the Specific Heats of Gases. 



95 



w 



1. 



2. 



3. 



4. 



5. 



6. 



60-43 



60-15 



60-73 



6010 



599 



6018 



!G 



19-10 



16-70 



17-95 



17*68 



1S-42 



17-77 



B 



75109 



751-09 



755-22 



755 10 



759-8 



759-8 



v 



2670 



26-52 



1918 



25-10 



26-38 



20-4 



x 



1780 



18-20 



18-20 



18-90 



17-80 



18-6 



n 



H 



n 



n 



93 



H 



4 



T 



174 



17-80 



1800 



18-7 



17-1 



182 



a 



5-77 



6-70 



513 



643 



526 



4-44 



T 



16-80 



18-00 



18-95 



18-22 



17-5 



1660 



m 



o-io 



010 



0083 



0-104 



0057 



0-08 



T, 



24-00 



24-54 



25-44 



2489 



2460 



24 01 



m l 



004 



005 



002 



0022 



-0018 



-0-004 



k 



0-095 



01084 



0-092 



00982 



0066 



00617 



« 



0-0083 



000764 



00097 



00123 



0197 



00114 







6-80 



6-005 



6-20 



6 3 



6-7 



652 



Oi 



6-62 



5-82 



602 



6134 



6-632 



6-38 



t 



2040 



2130 



22-30 



21-63 



2105 



20-14 1 



M 



99-70 



99-70 



99-80 



99-80 



100 



100 



e 



79-30 



78-40 



7750 



7817 



78-95 



79-86 



c 



3-336 



3-384 



3-333 



3-371 



3-413 



3-406 



The mean number deduced from experiments 5 and 6 is 

 3*410, the greatest deviation therefrom being 0*004. The 

 fact that the first four numbers are larger than the last two is 

 explained by Regnault's observation that the constant k acquires 

 a larger value when the whole apparatus is filled with hydrogen 

 (as was the case in the first four experiments) than when it is 

 filled with air. When the very mobile hydrogen is allowed to 

 remain at rest before and after the experiments, currents are 

 engendered which carry over heat from the heating-vessel to 

 the calorimeter, without taking into account the heat conducted 

 from the German-silver tube. But in making the correction, 

 the heat conducted over is alone taken into account, when the 

 apparatus is filled with a stream of gas, as the secondary cur- 

 rents are then entirely neutralized. But too great a value for 

 k causes the negative correction for the observed temperature- 

 increase to be also too large, and therefore the temperature- 

 increase itself to be too small. The smallness of the number 

 obtained for the specific heat is thus accounted for. 



In the last two experiments the apparatus was filled with air 

 before and after each experiment ; k has in these cases the 

 smaller and more correct value, and the number 3*410 then 

 obtained for the specific heat of hydrogen agrees well with 

 Regnault's number 3*409, especially when it is remembered 

 that his numbers vary from 3*401 to 3*419. 



By multiplying 0*9692 by 3*410 the number 0*2358 is ob- 

 tained as representing the specific heat referred to volume. 



It did not appear to be of interest to determine the specific 



