[36] Mackenzie attempted to ascend this hill, but was compelled to desist by clouds of musquitoes, (July 6th, 1789. _Voyage to the Arctic Sea_, p. 40.)
136 This limestone effervesces strongly with acids, breaks into irregular fragments, but with an imperfect slaty structure, and has a brown colour, with considerable l.u.s.tre in the cross fracture.
The specimens collected by Captain Franklin were as follows:--
144a Sandstone of an ash-gray colour, composed of rounded grains of semi-transparent quartz of various sizes, imbedded in a considerable proportion of a powdery basis which effervesces with acids. This bed weathers readily.
145 Thick-slaty sandstone pa.s.sing into slate-clay, having a very fine-grained earthy fracture, and a light bluish-gray colour. It is very similar to some of the softer sandstones that occur in the coal field at Edinburgh, particularly in the Calton Hill.
146 Sectile ash-gray slate-clay which forms the partings of the beds.
144b Bluish-gray marl, impregnated with quartz, forming a moderately hard stone, and containing corallines (_amplexus_.)
[37] _Upper part of the ramparts._
148 A fine-granular, foliated limestone, of a white colour, having large patches stained yellowish-brown, apparently by bitumen.
149 A yellowish-gray slightly granular limestone, with disseminated calc-spar.
150 Compact, white limestone, which, when examined with a lens, appears to be entirely composed of madrepores.
151 Specimens of limestone, having a crystalline texture, a brownish colour and slaty structure.
152 The seams are dark, as if from the carbonaceous matter--portions of this bed have the appearance of old mortar; but contain obscure madrepores.
_From the middle of the ramparts._
153 Fine-granular limestone, having a pale, wood-brown colour, and a splintery fracture. It resembles the limestone of the hill at the mouth of Bear Lake River.
154 Pale yellowish-brown limestone, with a dull fracture, but interspersed with small, shining, sparry plates, and traversed by concretions of calc-spar, that appear to have originated in corallines.
155 Yellowish-gray limestone, pa.s.sing into a soft marl slate.
156 Some beds contain a sh.e.l.l, which Mr. Sowerby refers, though with doubt, to the species named terebratula sphaeroidalis, a fossil of the cornbrash. The substance of the sh.e.l.ls is preserved.
Some of the specimens contain _producti_, and fragments of the coral named _amplexus_.
_Lower end of the ramparts._
157 Fine-grained limestone, of a dark-brown colour, containing some small, round, smooth b.a.l.l.s of dark limestone--occurs in horizontal strata.
158 Brownish-black flinty-slate, which forms a layer an inch thick, and covers the horizontal beds of limestone last mentioned. (157.)
[38] _Specimens from the cliffs in lat. 66-3/4 degrees._
159 Very fine-grained sandstone, with much clayey basis--portions of the bed iron-shot.
160 Sandstone fine-grained, and appearing, when examined with a lens, to be composed of minute grains of whitish translucent quartz, black Lydian stone, and ochre-coloured grains, probably of disintegrated felspar.
161 Rounded grains of nearly transparent quartz united without cement--this stone is friable.
162 Sandstone composed of grains like the preceding, united by a basis, and forming a firmer stone.
163 Hard, thin, slaty, bluish-gray sandstone, much iron-shot.
164 Fine-grained, bluish-gray sandstone, not to be distinguished in hand-specimens from some of the sandstones which occur at the rapid in Bear Lake River.
[39] _Horizontal limestone beds lying under the sandstone._
166 Fine-grained limestone, with an earthy fracture, coloured brown and grayish-white in patches.
167, 168 Similar stone to preceding, containing many sh.e.l.ls. Some beds contain only broken sh.e.l.ls.
169 Bed of imperfectly crystalline limestone, of a brownish-gray colour, traversed by veins of calc-spar.
170 Fragments containing madrepores and chain coral--occur amongst the debris of the limestone cliffs.
[40] _Sandstone cliffs twenty miles below Fort Good Hope._
173 Friable sandstone, composed of grayish-white quartz, in smooth, rounded grains, cemented by a brownish basis. Some carbonaceous matter is interspersed through the stone, and it contains small fragments of bituminous shale.
174 Calcareous sandstone pa.s.sing into slate-clay--bluish-gray colour.
175 Black, flinty-slate, with a flat conchoidal cross fracture. Some of the pieces appear to be rhomboidal distinct concretions.
176 Dull, flinty-slate, with an even fracture.
178 Thin-slaty blackish-gray sandstone, much indurated, containing scales of mica.
179, 180 Bluish-gray sandstone, containing many minute specks of carbonaceous matter; also, in patches, grains of chert, and flinty-slate, and imbedded pieces of iron-shot clay, which has obscure casts of sh.e.l.ls. Scales of mica are interspersed through this stone.
181, 182 Sandstone containing specks of bituminous? coal, and casts of some vegetable? substance.
183 Gray limestone, much impregnated with quartz, and having an imperfect crystalline structure.
[41] Mackenzie notices the precipices of "gray stone," which bound the river here, p. 71.
[42] See page 288.
[43] Specimens from Sellwood Bay.
202 Fine-grained dark brownish-gray dolomite, with corallines filled with white calc-spar.
203 Lucullite grayish-black, compact, and without l.u.s.tre.
204 Gray dolomite.
205 A rolled piece, evidently of the same rock with the preceding, containing the impression of a _cardium_.