1876.] 



Forms assumed by Drops of Liquids. 



269 



their number, when the height of fall was 150 millims., was gene? ally 

 24 ; but two or three having sometimes run together, made the estimate 



Set 9. 



I n 



uncertain. Incidental disturbing causes seem to alter the number of 

 arms, and to determine the tearing, regularly, irregularly, or not at all, 

 of the central patch in the case of higher falls. 



It may be objected that any results with so yariable a substance 

 as milk must be unsatisfactory. My object, howerer, was to study 

 the type of form before proceeding to quantitative measurements. For 

 these I am not likely for some time to have time or opportunity, which 

 is my excuse for presenting my paper as it is, in the hope that other and 

 abler observers may be attracted to the investigation. To the kindness 

 of Prof. Helmholtz, in giving me help and suggestions, much of the 

 success of my experiments is due. 



EXPLANATION OF THE FIGURES. 



The shaded parts throughout are sections. 



Set 1. 



Milk on smoked glass. Height of fall 37 millims. Diameter of drop 6*012 miUims. 

 Tlie shaded parts are vertical central sections, seen at an angle of about 30°. 

 I. Rises sometimes wavy, as in Ila. 



III. Smaller ; central hollow deeper; edge always wavj\ 



IV. The central hollow now fills up. 



IX. The wavy edge visible in the form of lobes as the drop contracts. 



Set 2. 



Milk on smoked glass. Diam. of drop 6'012 millims. Height of fall 50 millims. 



I. More spread out than from lower height. Edge wavy, as Ta or 1/3. Irregvilar 

 on unevenly smoked glass. 

 VII. The small detached drop flies upwards, while the remainder rises and splits 

 again as in the remaining consecutive phases. 



VOL. XXV. r 



