Finch on the Celtic Antiquities of America. 149 
According to this analysis, the essential constituents of 
this mineral are Bisilicates, and its mineralogical formula is, 
S?+-2 
S?. 
observes, that the analyses of different specimens show, 
“that all minerals which have the crystalline form of py- 
rg, in Wermeland,” which yielded 4.99 per 100 of Mag- 
hesia, he says expressly, “if ihe magnesia is not taken into 
Consideration, this pyroxene belongs to the second divis- 
lon,” viz. to that of “ pyroxenes with lime and protoxide 
of iron as bases.”’ 
ANTIQUITIES. 
anpeelerin 
Art, XX.—On the Celtic Antiquities of America. By 
Joun Fincn, F. B. S. &c. Professor of Geology a 
Mineralogy. 
From our earliest infancy we are aceustomed to admire 
every thing connected with ancient times. The sentiment 
Seems implanted in our nature, and if the monuments we 
per 7te Proportions of the silica obtained from i trials, were 
» Ist. 45,333—2d. 45. -333._ In my 
ments, the magnesia was detected, after the silica had been gern 
treating the liquor wi excess of sub-carbonate of ammonia; cag sep- 
rating the precipitate, the liquor was treated with ammonia, @' phos- 
Phate of soda ; ammoniacal phosphate of magnesia was precipi 
t Annals of Philosophy, new series, for March 1823, p. 224. 
¥ Annals of Philosophy for March 1823, p. 227. 
