410 Mr. T. Proctor Hall on New Methods of 



much reduced that it was evident that the surface had become 

 contaminated. I have reason to believe that only the first 

 two, if any, of the observations were made with a clean 

 surface, and have therefore in the fourth column given the 

 values calculated by the formula 



T = 75-48 --140* dynes 



obtained by taking the first two observations only. 



Weight (in 

 grains.). 



Temp. 0. 



T found. 



T calc. 



Difference. 



•8044 



o 

 01 



75-468 



75-466 





•7859 



125 



73-733 



73-730 





•7836 



13-8 



73-52 



73-55 



•03 



•7795 



162 



7313 



73-21 



•08 



•7742 



19-5 



72-63 



72-75 



•12 



The width of the frame was 5'2321 centim., and its capil- 

 larity correction *0075 centim. The same frame was used 

 for the following observations, which were made at different 

 times for the purpose of finding the effect of dissolved air 

 upon the surface-tension. The first seven of the following 

 measurements were made with fresh portions of the same 

 w r ater as the foregoing. In the last column they are reduced 

 to 18° C, at which the surface-tension according to the 

 formula given above is 72*96 dynes. 





Weight (in 

 grams). 



Temperature. 



T found. 



Tat 18°. 



1. 



2. 

 3. 



4. 

 5. 

 6. 



7. 



•7762 

 •7753 



•7748 

 •7752 

 •7750 

 •7766 



•7772 



18-37 

 19-90 

 20-60 

 18-64 

 19-32 

 17-85 

 18-35 



72-82 

 72-74 

 72-69 

 72-73 

 72-71 

 72-86 

 72-92 



72-87 

 73-00 

 73-06 



72-82 

 7289 

 72-84 

 72-87 



8. 



9. 



10. 



•7813 

 •7780 

 •7697 



15-97 

 17-76 

 19-60 



73-30 

 72-99 

 72-21 



73 02 

 72-96 

 72-44 



