286 Inquiries concerning the Mode of the 



individual particle of a liquid can never be put in mo- 

 tion in consequence of a change of its specific gravity 

 occasioned by a change of temperature, yet what cannot 

 happen to a single particle may easily and must neces- 

 sarily happen to small masses of the liquid consisting 

 of a great number of these particles united, as is abun- 

 dantly proved by the currents which are so easily excited 

 by the contact of a hot or cold body plunged in a 

 liquid. 



The force by which the particles of liquids adhere to- 

 gether is very great, and it is more than probable that it 

 is the cause of many very interesting phenomena, and 

 amongst others of the suspension of the heavy bodies 

 which much lighter liquids so frequently hold in solu- 

 tion. 



From the result of an experiment which I made some 

 years ago in order to determine the measure of the vis- 

 cosity or the want of perfect fluidity in water at the tem- 

 perature of 64 F., I found reason to conclude that a 

 solid body, having a surface equal to 368 square inches, 

 which should weigh only one grain Troy more than an 

 equal volume of water, would remain suspended in that 

 liquid ; and from this datum it is easy to find by calcu- 

 lation what ought to be the diameter of a small solid 

 spherule of the heaviest matter, of gold, for instance, 

 in order to its remaining suspended in water in con- 

 sequence of the viscosity of that liquid. 



Having made this calculation in order to satisfy my 

 curiosity, I found that a solid spherule of pure gold, of 

 the diameter of ^"oWir ( or exactly ^-g-grT^) f an i ncn > 

 ought to remain suspended in water in consequence of 

 the adhesion of the particles of that liquid to each other. 

 But I shall return to this subject on a future occasion. 



