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



Ethylene. 



The ethylene was produced by Mitscherlich's method, viz. 

 by leading alcohol vapour into tolerably concentrated sulphuric 

 acid heated to 100° or 170°. The gas was cooled to condense 

 ether, which is always produced along with the ethylene, and 

 then passed through caustic potash and through concentratec 

 sulphuric acid into a gasometer. The last traces of ether were 

 given up to the water in the gasometer ; and the gas, after 

 being dried by means of sulphuric acid, could be passed into 

 the caoutchouc balloon. 



Inasmuch as by-products are always formed in the produc- 

 tion of ethylene, so great an agreement among the results of 

 experiments cannot be expected in the case of this as of the 

 other gases. 





Table I. — Experiments between 100° and 25°. 







1. 



2. 



3. 



4. 



5. 



6. 



7. 



8. 



w... 



60-4 



60-51 



60-9 



60-88 



60-7 



60-88 



60-73 



60-29 



Q ... 



14-95 



15-68 



15-4 



161 



15-25 



1613 



17-72 



1511 



B ... 



7487 



748-4 



748-4 



748-4 



750-84 



75084 



750-84 



748-3 



p ... 



80-37 



81-20 



82-42 



7426 



78-33 



78-33 



7915 



80-8 



X ••• 



20-8 



21-8 



21-8 



21-6 



21-8 



22-2 



231 



22-9 



n ... 



3 



3 



3 



H 



3 



3£ 



H 



3 



a ... 



5-00 



5-22 



51 



4-92 



5-08 



5-34 



506 



5-03 



T ... 



21-20 



21-9 



22 



21-7 



21-9 



22-2 



22-75 



25 



T ... 



2112 



20-23 



19-23 



2025 



18-55 



1811 



20-05 



19-84 



m ... 



0071 



0-073 



0-094 



0-088 



0-1 



0137 



0-068 



0115 



T x ... 



29-54 



2914 



28-37 



29-4 



2715 



27-8 



30-06 



29-19 



m,... 



-0-056 



-0-047 



-0-02 



-0-057 



-0-017 



-0-033 



-0-06 



-0-036 



h ... 



0-070 



0-050 



0-059 



0-064 



0-0554 



0046 



0033 



0-0632 



K, 



0-015 



0-0134 



00124 



0-0158 



0-0136 



00141 



0-0128 



0016 



... 



8-26 



8-74 



8-98 



91 



8-3 



937 



9-98 



9 



d 1 ... 



8-25 



8-71 



8-88 



9-07 



8-18 



9-27 



9-98 



8-9 



t ... 



25-57 



24-93 



23-96 



2515 



23 



23-21 



25-30 



24-75 



M... 



100-65 



100 



101 



102 



97 



1005 



100 



102-1 



... 



751 



75-07 



77-1 



76-85 



74 



7729 



74-7 



77-35 



c ... 



0-3803 



0-3852 



0-3912 



0-3867 



0-3783 



0-3896 



0-3950 



0-3973 



Mean value =0*3880 ; greatest deviation =0*0093. 



