185 
TAB. CCXCIV, 
BARYTES sulphata. 
Sulphate of Barytes. 
Div. 2. Imitative. 
When we are showing any distinct subject, it is often 
necessary, for the sake of comparison, to exhibit others that 
bear analogy to it, and may be confounded with it. Fre- 
derick Hall, Esq., whose kindness gave me an opportunity 
of showing the best specimen of crystallized Carbonate of 
Barytes, tab. 76, favoured me with this specimen of Sul- 
phate from Arkendale in September 1805. It now seems 
to be an appropriate time to exhibit this, and the pleasure [ 
have in doing so may perhaps only be felt by those who 
occasionally share such friendly favours. It is, if I may 
use the term, a vermiculated Sulphate of Barytes, or some- 
what like Sabella rudis, which accumulates bits of shells, 
as if an abundance of worm gluten, having accumulated 
every thing in its way, found chiefly Sulphate of Barytes 
to adhere to it. It is. composed of irregularly formed 
tubes, many of which are distinctly angular with from 
three to five angles, the tubes curving and passing over 
each other in every direction in a crowded manner. When 
the present specimen was sent, Mr. Hall observed he could 
have sent a very large mass but for the great weight and 
bulk, it being as big asa bushel. 
Primitive Crystals of Sulphate of Barytes are rather rare. 
These tubes are nearly covered with them both‘on the in- 
side and out, the tubes being rather opaque. Those within 
