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Jan 1, 1922

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By Persifor Frazer

Comparative columns expressing the series of rocks of the lower half of the Mesozoic age in this country and in Europe are not yet definitely established. The following represents a co-ordination of the beds in England and Germany,* with a list of materials to be worked in from this country .†

By John C. Long

The advantages of firebrick regenerative hot-blast ovens being thoroughly appreciated by those engaged in modern blast-furnace practice, the important question now is to obtain the best and most efficient apparatus. The apparatus invented by the writer, and described in this

Jan 1, 1885

Jan 1, 1935

By George H. Cook

At first sight this subject seems to belong to pure theoretical geology, but examination will soon show that it has important practical and economic interest to the mining engineer. The conclusion that all the northern portions of our country, as well as of the eastern continent, have, in the later periods of geological history, been covered with a thick bed of ice, is now accepted by geologists. This bed of ice, except in its greater magnitude, was like the modern glaciers of the Alps, and other mountains which extend above the line of perpetual snow. The marks it has left upon the surface show that it was comparatively thin on its southern edge, but that its thickness was much greater a little further north, and that it was several thousand feet thick at its kenviest parts. This variation of its surface would give it a descending slope towards the south, and cause the mass of ice, like a semifluid substance, to move in that direction,

Jan 1, 1879