a = m ye. § Hunt on Ophiolites. 
ing, Shile by the same process the unignited mies gave 
pone of ae fa a large amount of m 
30 yn 
ace Tes 
ue from the action of acetic acid, rege I however 
: Mi of iron, - - . ~ ‘ 8°69 
Loss sd ignition, - - - - - 1450 
99°23 
2. A dull reddish brown ophiolite, - the same locality as 
the last, likewise contained a small amount of disseminated car- 
bonates, which were completely removed. iy acetic acid. Thus 
‘Purified, the matter gave on analys 
Sili . . : - 39°80 
Magnesia (by. difference), - - - 8°40 
Protoxyd o of iron, - - - - 7 92 
Loss by ignitio: - . “ - - 1880 
10000 
‘The dark color and opacity of this rock seem to be due to the 
presence of disseminated peroxyd of iron, to which some for- — 
. ophiolites appear also to owe their red colors 
. pale greenish gray ophiolite, nearly 0 aque, soft, and 
in its aspect, occurs at the Calumet Island, on the Ottawa, 
being sought ‘after by the Indians, who fashion the pris 
into ae or given the pene i to a Island. It 
contains no lime, ee shor ignition, yields a to 
solution of nitrate of ammonia. Sas. ue a mix- 
~ ture of an Eel matter; it pve: — ee 
ee ; Sk | SEBO 
Magnesi. a 
Gircee and ond of seis - . 
by ignition, ; 
upon their surfaces, W! pgp 
que. The | ai ®: ne of which were one-ten 
aS ante el rena snd eae low 
é u Z = 4410 
eis * — ee e se Y rae L165 
Oxyd of iron and alumina, = Sen: te Tel 
Loss by ignition, - ae coca 
100°00 
