4 
1 
‘ 
. 
. 
: 
Native Copper of Wallingford. 55 
Professor Mitchill, who found it exclusively composed of mag- 
nesia and carbonic acid. _Carbonates of magnesia, hitherto 
discovered, have been, I believe, found impure, and in a state 
of rock, requiring chemical process to render them service- 
able ; this is, perhaps, fit for immediate use. When I first 
mentioned the discovery to mineralogists, they were increda- 
lous, supposing it did not natively exist in this state, but I con- 
vinced them by uniting it with sulphuric acid. 
REMARKS. 
The specimen of amianthus, referred to in Mr. Pierce’s 
communication, is uncommonly beautiful. The fibres measure 
12 and 15 inches in length, and are as soft and flexible as fine — 
human hair. ase 
It will be remembered that in the rocks at Hoboken, Dr. 
Bruce discovered the hydrate of magnesia, or magnesia com- 
bined with nothing but water, in the proportion of about 70 
per cent. of magnesia. This discovery gave a new and inter- 
esting species to mineralogy; itis now admitted in the sys- 
tematical works on mineralogy. 
Mr. Pierce’s discovery is not less interesting ; and we pre- 
sume he will be deemed correct in the opinion, that pure na- 
tive carbonate of magnesia has not been discovered before. The 
Serpentine of Hoboken, then, is memorable for affording these 
two new species, 
is 8 eae 
Art. V. Native Copper. 
ly Bruce’s Journal, (Vol. I. p. 149.) mention is made of a 
remarkable piece of native copper, found near New-Haven 
many years ago, and weighing about 9U|bs. 
: We have now to add, (and the fact is, indeed, mentioned 
mM Cleaveland’s Mineralogy,) that another piece has been 
recently found half a mile west of the Hartford turnpike 
road, Opposite the town of Wallingford, and twelve miles 
ftom New-Hayen, It was turned up in ploughing to repair a 
