RESULTS OF THE VOYAGE OF H.M.S. PENGUIN - . 
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Appendix A. 
Geological Observations at Red Cliff's, near Cossack, N. W. Australia. 
On April 25, 1891, I landed at the “Red Cliffs/’ between Cape Lambert and 
Reader Head, near Cossack, N.W. Australia, and made the following notes on their 
geological structure 
(1.) The cliff runs in a general N.W. and S.E. direction for about a quarter of a 
mile, and is about 30 feet in average height; the face is very rugged, but it being 
almost entirely free from vegetation, some very excellent sections are presented. 
(2.) At the N.W. end (A in the general sketch), the beach is strewn with huge 
blocks of breccia and ironstone conglomerate, fallen from the cliffs above. Commencing 
from high-water-mark (it being unfortunately nearly high tide when I landed), there 
is first a layer of yellowish sandstone (?), about 10 feet thick, the bedding of which is 
nearly horizontal. On this rests another bed of the same thickness of a siliceous 
breccia, crowded with angular fragments of various forms of quartzite. At the top of 
this layer, the paste in which the fragments are embedded becomes highly ferruginous, 
and passes into a cap of “ironstone conglomerate,” consisting of rounded nodules of 
(apparently) brown haematite embedded in a reddish-brown paste, which effervesces 
strongly when treated with hydrochloric acid. 
(3.) Proceeding along the cliff to (B), large masses of compact ironstone (? brown 
haematite) in situ are seen, cropping out of the beach at high-water-mark. 
(4.) At (C) is a small gap in the cliff, just beyond which is a well-marked dyke¬ 
like mass of quartz, about 4 feet wide, in layers alternately light and dark coloured, 
and bedded almost vertically. The “ strike ” of these layers is approximately N.E. 
and S.W. On the north side of the dyke-like mass is a narrow platform of ferruginous 
sandstone, having the same dip and strike. At (C) is a small mass or vein (marked 
X in general sketch) of a curious whitish soft mineral, which I am not able to name. 
(5.) At (D) the cliffs are intersected by a very remarkable dyke-like mass, or vein, 
of compact ironstone, about 20 feet in width, nearly vertical, strike about N.N.E. and 
S.S.W. It appears to be continued out to sea in the same direction in a series of 
reefs, awash at low water. Just beyond it, at (E), is another dyke-like mass of 
quartzite, similar to that at (C), but the layers are better defined, and in places much 
more contorted ; the width of this dyke-like mass is about 10 feet. Here the cap of 
ironstone conglomerate ceases. 
(6.) A little further on, in a small hollow or glen in the cliff, another massive dyke¬ 
like mass of ironstone, similar to that at (D), crops out. Then comes, at (F), a mass 
of “ ironstone breccia ” (fragments of quartzite embedded in a highly ferruginous 
paste), which passes at (G) into what 1 venture to call “ ironstone schist,” consisting 
of alternate layers of whitish quartzose stone and ironstone, about an inch in average 
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