cclii 
APPENDIX. 
— loss 1.14<. Its specific gravity Mr. Children found to be 2.67. Before the 
blow-pipe it melts into a milk-white enamel. Its colour is a dirty yellowish 
green, passing into brownish. It is scratched by the knife ; streak white. 
Fracture uneven, dull, approaching to resinous ; here and there with small 
planes of cleavage, which are shining, and even splendent. It is rather 
easily frangible ; the fragments are indeterminately angular, and translucent 
at the edges. This substance, which I suppose constitutes a distinct species 
among the silicates of sodium, appears to be one of those which enter the 
composition of the rock called Gabbro by Mr. Von Buch. 
As probably connected with this formation we may consider the magnetic 
iron-stone, of which some specimens were gathered in lat. 72° long. 90° 
west ; it is of a very fine grain, and occurs also disseminated in, and alter- 
nating with, granular quartz, exhibiting white and grey stripes. Some 
specimens also of jaspery ironstone, mixed with particles of quartz, were 
found on the eastern coast of Prince Regent’s Inlet. Nor is the presence of 
iron less observable in specimens referable to more recent formations of trap 
from the same quarter, such as various kinds of clay ironstone, and ferru- 
ginous sandstone. Of the latter of these a greenish-grey variety appears to 
be of particularly frequent occurrence in those parts ; if we are allowed to 
judge from the many, especially tabular, fragments brought from thence, 
which are all, more or less, impregnated with brown hydrous oxyde of iron, 
some being so completely penetrated by it that they may be considered as 
tolerably rich ores of this metal. 
As it is sufficiently difficult to judge of the relative antiquity of depositions 
of sandstone, when observed in situ, it would, of course, be altogether una- 
vailing to indulge in conjectures respecting the formations to which the 
fragments and rolled pieces may have belonged which were picked up in 
various parts of the north coast of Barrow’s Strait, and Prince Regent’s Inlet. 
The most abundant among them is a red sandstone, and a variegated 
one with brownish-red stripes. These varieties are seen to pass into one 
another: they are composed of small grains, united by a quartzy cement. 
