whofe fuperfici^ ended in fuch points as I have before 
mentioned. 
Fig. I. A B C D E F (hews you one of the faid Cry- 
ftal Particles, wherein you may obferve at ABC, and 
partly alfo between D F how it had been joynd, and how 
alfo it had been broken off from other Cryftal [Particles ^ 
between D E F is that part from whence proceeds feveral 
prominent points, which the Painter has defcrib*d to the 
beft of his power. 
Fig. 2. GHIKLMN Rcprefents a larger Particle of 
Cryftal which had been joyn d to another Particle lying 
by it 3 as in G H I K O is (hown that part that had not 
been united, and in which, as far as it is poffible, the 
feveral prominent Points are defcrib'd by L M N G O. In 
handling thcfe foremention'd Cryftal Particles, I found that 
they were feparated from one another with very little 
trouble 5 to make a further proof of the fof tnefs thereof, 
I plac'd a Particle of it no bigger than a grain of Sand up- 
on a Plate, and then preffing it with my Thumb Nail, it 
burft into a thoufand fmall pieces, which feem*d the 
ftranger to me, becaufe we know generally how hard the 
Mountain Cryftal is. 
From this Experiment, I imagined, that what we call 
wild Cryftal is moftly Salt, if perhaps it be not all fo. 
To make a further tryal thereof, I took a piece of the 
faid Cryftal about the bignefs of a Pea, which I broke crfF 
from a Flint Scone, and laid it upon a Silver-Smith's Wood 
Coal, and put it into a glowing heat, and then threw it 
into fome clean Rain-Water, whereby it was immediately 
diflblv'd into white Powder 5 but viewing the fame with 
my Microfcope, I faw that there remain d fome Particles 
ftill as big as a grain of Sand. 
The fmall quantity of Water in which the Cryftal lay, 
that was no more than could be contained in a little Thim- 
ble, having ftood about a quarter of an hour, I obferv'd 
that the fuperficies of it was cover d with a thin Scum, of 
which taking a fmall part, (as I did again when the feid 
Scum 
