480 



Prof. Guthrie on Drops. 



[Recess, 



creep back along its outside, and so give rise to an irregular drop-base. 

 Water was made to drop through A, fig. 1 1, at the same rate, gt—2^\ and 

 through the same liquids as before, namely T, BT^, BT, B^T, B. The 

 same measuring-tube was used as in tig. 10, or Table XVII., and it was 

 filled to the same point. Correction was made for meniscus. 



Number of drops. 





Table XVIII. 





















T=24°-5 C. 









T. 



BT,. 



BT. 



B^T. 



B. 



r256 



218 



178 



162 



87 





220 



177 



164 



86 



256 









86 











86 



256 



219 



177-5 



T63 



86-2 



We may now compare Tables XVII. and XVIII., since the conditions 

 of the experiments whence they are got are identical. The drop-sizes are 

 inversely as the drop-numbers. Let us use the symbol X^ to denote the 

 drop-size of the liquid X through medium Y, &c. Comparing, first, the 

 size of a drop of X through medium Y with tlie size of a drop of Y through 



medium X, or finding the values of we have (putting W for water) 



Table XIX. 

 We 103-7 



B^v 86-2 

 Wb,t^205-7 

 B/r^ 163 

 Wt^t. 230 



= 1-203. 

 1-262. 



= 1-296. 



BTw 177-5 



= 1-149. 



Wbt,_251-7 



BT2 219 



Hence in none of these cases is the drop-size of one liquid through an- 

 other equal to the drop-size of the second through the first. We get the 

 general law, that — 



If the liquid X has a larger drop-size than the liquid Y in the liquid Z, 

 then the liquid Z has a larger drop-size in X than it has in Y. Further, — 



If a liquid X has a larger drop-size than a liquid Y in air, then the 

 drop-size of X through Y is greater than the drop-size of Y through X. 

 Again, — 



If the drop-size of^be greater than the drop-size ofY, and the drop- 

 size ofYbe greater than the drop-size of Z in air, then the ratio between 

 the drop-sizes of X in any mixture of Y and Z, and the drop-size of that 



