of Liquids to each other. 303 



liquid by a very great surface (about 550 square inches), 

 and its loss of weight on account of the viscosity of the 

 liquid was very sensible ; but when it was weighed in a 

 small vessel which had been previously counterpoised 

 very exactly in the water, the arm of the balance sup- 

 ported all the excess of the weight of the silk over that 

 of an equal bulk of water without any diminution. 



The results of these experiments have furnished data 

 for calculating, with sufficient exactness, the degree of 

 force with which particles of water adhere to each other, 

 when it is a question of causing them to move one 

 upon the other at a temperature of about 60 F., and I 

 found it to be such that a solid body specifically heavier 

 than water, having a surface equal to 368 square inches 

 (English), when submerged in water, ought to lose in 

 weight, on account of the viscosity of the water, an 

 amount equal to I grain Troy. 



The discovery of this fact has put me in position, not 

 only to prove that all bodies in nature, the heaviest as 

 well as the lightest, can be suspended and supported 

 in still water, on account of its viscosity, provided they 

 are reduced to a sufficiently small size, but also to deter- 

 mine by calculation that a solid spherule of gold about 

 STTiF^nnr f an ^ ncn ' m diameter would remain sus- 

 pended in this manner, as I have already announced to 

 the Class in the memoir read at the session held on the 

 1 6th of June, the past year (1806).* 



Having announced facts as remarkable as these, I re- 

 frained from entering into more minute details. I did 

 not even think it necessary to observe that, even if I 

 should have deceived myself somewhat in my estimation 

 of the force of cohesion of the particles of water, still, if 



* This calculation will be found in a note at the end of this paper (page 315). 



