ON VINEGAR. 



1 HAVE obferved, tliat on expofing a fmall quantity of white 

 wine Vinegar to the air for a few hours, a vaft number of corpuf- 

 cles, or fmall folic! fubfianccs appear in it, which I take on mvfelf 

 to name the falts of Vinegar. Some of thefe are reprefented in 

 Plate V. fig. I o ; thofe at A appeared to terminate in a Iharp 

 point at each end, havuig in the middle a dark fpot ; others were 

 glittering like cr}-Il:als, as at B, and thefe were mofl in number : 

 others of thefe corpufcles were of an oblong figure, and of a dark 

 colour, with a lucid fpot in the middle, as at C ; and fome few 

 of an oval form witli an oval bright fpot in the middle, as at D. 

 Among the figures A, B, D, I was convinced that I faw feveral 

 with a cavity or hollow in them, which gave them the appearance 

 of being iialf dark coloured, and half tranfparent. Others of thefe 

 falts or cryftals laid one on another in clu Iters, as at E ; and lafi:ly, 

 fome there were with points at one end only, like half cryfials, 

 as at F. It is not eal'y to defcribe the extreme minutenefs of thefe 

 corpufcles, and fome of thera were indeed, fo fmall that tliey 

 almofi efcaped the view of the microfcope. 



All thefe particles, which I name the fait of vinegar, I conclude 

 to be thofe parts of it which excite on the tongue that tafie or 

 fenfe named acid. And, althougli they appeared to me, through 

 the microfcope, of the fliapes and fizes I have mentioned, yet 

 I concluded that thev were all compofcd of ftill fmallcr par- 

 ticles, of the fame fliape, in like manner as I have often in our 

 common fea-water, or in water wherein common fait is dilTolved, 

 when placed before a microfcope, feen many particles molt 

 exactly quadrilateral, or four-lquare, but lo minute that millions of 



