( K^iJ ) 
than the Hair of a M^ms liead 5 they were of a dark grey co- 
lour, and had at one end feveral thinner Particles, or little 
Fibres branching fome others were much finer than the 
fingle Hair, and fome of them of exceeding finenefs. 
In another and thicker Cryftal, I faw above five and 
twenty more fuch long Particles^ and notwithftanding that 
I broke thit Cryftal into pieces, to difcover of what 
Matter thefe Particles were compofed, yet I could not fuc- 
ceed therein. I faw indeed that one of em had a fort of a 
Cavity in it, and was round, another flat without any 
hollownefs, and in another piece of the broken Cryftal I 
could perceive a Triangular long Particle that was hollow 5 
this lafl was very vifible, becaufe one end of it lay oppofed 
to my fight. I faw alio another very, plainly that was 
Triangular likewife, two fides of which were a third part 
broader than the other ^ but I was not very fare that it was 
hoilow : I faw a!fo another long Particle that was Quadra- 
lateral, of which the two oppofite fides vvere twice as broad 
as the other two^ and forafmuch, as I was well aflured, that 
it could never have been any Hair or Particles of Wool., 
nor had I ever feen any Vegetable that had produc'd fuch 
fine flender Parrs, I could not come to any conclufion what, 
for a fubrtance it was, and much lefs how they could come 
into the Cryftal, ia which they lay acrofs or athwart one 
another. 
I have cbfervy • before^ that when I piac'd fuch Rock 
Cryftal over the Fire, it burft into a great many , pieces 5 
from whence I inferred, that in the fame there mufl: be fnut 
up either fome Vapour, or elfe Particlesof Salt, that occafi- 
on'd its breaking inio fo many pieces 5, to difcover which, 
I pot into a little Glafs feveral pieces of fuch broken Cry« 
ftai ^ and obfery'd that by the Fire a very little Moifture 
and Salt was drawn off from the fame ^ but when I threw 
fome of thofe pieces of Cryftal, as glowing hot as I could 
make them, into Water, I could not difcover, as i had 
done 
