654 PLATEAU ON THE PHENOMENA OF A FREE LIQUID MASS 



constrictions (§ 53) ; the proportion of the length of a division to 

 the diameter of the eyhnder cannot then be less than the limit 

 of stability ; and we may remark here that this conclusion is 

 equally true, whether the divisions are able or not to assume 

 exactly their normal length. 



58. Let us now attempt to ascertain the influence of the nature 

 of the liquid and that of external circumstances, commencing 

 with the latter. Our liquid cylinder of mercury, along the 

 whole of the line at which it touches the plate of glass, must 

 contract a slight adherence to this plate, which adherence must 

 more or less impede the transformation. To discover whether 

 this resistance exerted any influence upon the normal length of 

 the divisions, consequently upon the proportion of the latter to 

 the diameter of the cylinder, a simple means presented itself, 

 viz. to augment this resistance. To arrive at this result, I 

 arranged the apparatus in such a manner as to remove only one 

 of the strips of glass, so that the liquid figure then remained 

 simultaneously in contact with the plate and the other strip. 

 I again repeated the experiment ten times, using copper wires 

 1*05 millim. in diameter, and giving the cylinder a length of 

 100 millims. The following were the results : — 



Number of 

 isolated 

 spheres. 



Masses adherent to the bases. 



One large and one small. 

 One large and one small. 

 One large and one small. 

 One large and one small. 



Two small 



One large and one small. . 

 One large and one small. 



Two large 



One large and one small. 

 Two large 



Length 



of a 

 division. 



znillims. 



1000 



1111 



1000 



nil 



8fi9 

 1111 



nil 



10-53 



11-11 



13-33 



It is evident that the different values of the length of a divi- 

 sion, with a single exception, are all obviously greater than all 

 those which relate to a cylinder of the same diameter, the sur- 

 face of which only touches the glass by a single line (§ 54). We 

 must thence conclude, that, all other things being the same, the 

 length of the divisions increases with the external resistance, 

 consequently, under the action of the same resistance this length 

 is necessarily greater than it would be if the convex surface of 

 the cylinder had been perfectly free. 



