382 ESSAYS AND OBSERVATIONS 



eft philofophers of the laft and prefent 

 age. The curious experiments of the in- 

 genious Dr Hales, in his Analyfts of the Air, 

 and the furpridng experiments on eledri- 

 city, now fo much in vogue, may fatisfy 

 us, that particles of the fame nature and 

 qualities with thofe of air and light, may 

 bejoined to particles of a groffernature and 

 attractive quality, in various maffss of 

 matter, to fome adhering more loofely, to 

 others more firmly conne(5led. For fome 

 time, they may lie concealed without ma- 

 nifeft motion or acflion, t'leir repelling or 

 elaftic power being overcome or balanced 

 by the attradive force of che iurrounding 

 corpufcles, till, by certain concurring cir- 

 cumftances, as external motion, heat, 

 moiflure, the addition of other matter, 

 (6^<:. the attra(5live force is diminifhed, 

 or the repelling increafed : Then they are 

 roufed, as it were, into adlion, and difco- 

 ver themfelves by great and remarkable 

 efFedls, in changing the texture of the 

 niaffes to which they were united. Such 

 changes wc daily fee happen in fermen- 

 tations. 



