Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/351

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mentions a tunnel, 430 feet above the sea-level, bored through the whole thickness of one of the seams for a distance of between 150 and 250 feet. A cross tunnel near the mouth of this reached coal at a distance of 50 feet. The coal is carried down to the shore by men, mules, and ponies ; its price on the spot is 4 dollars per ton.

Mr. Adams also stated that, from what he had heard, there are unworked coal-seams in the neighbourhood of Otarunai, and indications of lead, copper, and even gold in various parts of the island.

2. On a Peculiarity of the Brendon Hills Spathose-Iron-Ore Veins. By M. Morgans, Esq.

(Communicated by Warington W. Smyth, Esq., F.R.S., V.P.G.S.)

[Abridged.]

According to the author the Brendon Hills consist of a Devonian Slate, dipping about S. by E. at 30°, and N. by W. at 60° on the two sides of the axis of elevation. The cleavage-laminae dip nearly S. by W. at 80° ; and the cleavage-strike varies but little from E. by N. and W. by S., forming only a slight angle with the main axis of elevation.

The clay-slate of the Brendon Hills contains very fine lenticular veins of spathose iron- ore exceedingly rich in manganese, the dip and strike-lines of which are not influenced by irregularities in the strata, but for the most part follow the direction of the cleavage-planes, although, as they are often tortuous, they do not constantly coincide with them (fig. 1).

Fig. 1. — Cross Section of a Vein.

The dotted lines represent the cleavage. bbb. Bedding lines, vv. A vein at about the average dip.

The depth of the veins has not been ascertained. The main ones extend for several miles in length, sometimes dividing and reuni-