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sections, constructed from surface exposures, indicate that the probable depth of the coal horizon is not great over a consider- able area between Camp Robertson and Yakoun lake.

The probability of a coal seam being found at this horizon throughout the Honna basin, remains to be considered. The evidence on which the conclusions are based will in part be sum- med up later. There appears to be no good reason to expect that a seam of better quality than the one now known will be found. The measures on the whole are variable and made up of hastily accumulated material; and the coal seam bears evidence of rapid changes in conditions of deposition. These conditions in the Honna basin do not appear to have been favourable for the ex- tensive accumulation of vegetable deposits. The finding of coal seams in various localities, already enumerated, in different parts of the western and northern portions of the Honna basin, is good evidence that a single seam, ora series of overlapping seams occur there. The western portion of the seam or seams has been so altered by volcanic agencies that it cannot at present be econom- ically mined, even in the few localities where the coal is of sufficient thickness.

About Camp Robertson the seam is at its best as far as qual- ity goes, but the structure is complicated by folds and faults. Between Camp Robertson, Yakoun lake, and the ridge surmount- ed by Mount Etheline there is a considerable body of coal which apparently is fairly regular in its structure; but, from the char- acter of the seam at Camp Robertson, the quality of this coal cannot be expected to be high.

The question of the extension of the Robertson seam down the Honna valley is a difficult one to answer. No trace of the seam has been seen on any of the creeks in the territory in which the horizon outcrops, except on Honna river, where some coaly shale occurs. The massive sandstones of the upper Haida do not extend down the Honna valley, and in this valley and on the west shore of Bearskin bay the upper half of the Haida formation is shaly and thin bedded, and more fossiliferous than around Camp Robertson. The evidence is unsatisfactory because the actual conditions of the accumulation of the coal are not known; but conditions of deposition were different in the eastern part of