WITHDRAWN FROM THE ACTION OF GRAVITY. 669 



in air, of sufficient length to furnish several spheres, its convex 

 surface being entirely free, and its length such that the divi- 

 sions assume exactly their normal length, the time which will 

 elapse from the origin of the transformation to the instant of the 

 rupture of the lines will be exactly or apparently proportional 

 to the diameter of this cylinder. 



2. The same very probably applies to a cylinder formed of 

 any other very slightly viscid liquid, as water, alcohol, &c., and 

 supposed to exist under the same circumstances. 



3. It is possible that this law is completely general, i. e. ap- 

 pUcable to a cylinder formed, always under the same circum- 

 stances, of any kind of liquid whatever ; but our experiments 

 leave us in doubt on this point. 



66. Let us now enter upon the consideration of the absolute 

 value of the time in question for a given diameter, the cylinder 

 always being supposed to be produced in vacuo or in air, of suf- 

 ficient length to furnish several spheres, its entire convex surface 

 free, and its length such that its divisions assume their normal 

 length. It is clear that this absolute value must vary according 

 to the nature of the liquid ; for it evidently depends upon the 

 density of the latter, upon the intensity of its configuring forces, 

 and lastly upon its viscidity. The experiments which we have 

 detailed give with regard to oil a very remote superior limit ; 

 this results, first, from the two causes which we have men- 

 tioned in § 64, and which are due to the presence of the alco- 

 holic liquid ; but with these two causes is connected a third, 

 which we must make known. If we imagine a cylinder of oil 

 formed under the above conditions, the sum of the lengths of 

 a constriction and a dilatation will necessarily be much greater 

 in regard to this cylinder than in regard to one of our short 

 cylinders of oil of the same diameter; for in the former this 

 sum is equivalent to the length of a division ; and in consequence 

 of the great viscidity of the oil, this latter quantity must greatly 

 exceed the length corresponding to the limit of stability. Now, 

 it may be laid down as a principle, that, all other things being 

 equal, an increase in the sum of the lengths of a constriction 

 and a dilatation tends to render the transformation more rapid, 

 and consequently to abbreviate the total and partial durations of 

 the phaenomenon. In fact, for a given diameter, the more the sum 

 in question differs from the length corresponding to the limit of 

 stability, the more the forces which produce the transformation 



VOL. V. PART XXI. 2 Z 



