No coin nor oath required. For personal study only.
๐ SIMILAR VOLUMES
On p. 513, line 15, column 1, read "(a//2[110]" instead of " (a/2[ilO]".
## Influence of ,Shape ~+po~ Attraeliom 207 Swiss Anthracite.--Late analyses of the anthracite coal of Vah)is show about 90 per cent. of c'~rbon and hydrogen and 81 per cent. of ashes. Experiments with American heaters show that it is capable of replacing the Pennsylvania coal, which is sometimes i
## Phosphorus in Iron and Steel.--Melted pig iron and iron oxide, melted in a cupola, are mixed together, by Bell, in a revolving puddling furnace, at a moderate temperature, when the phosphorus oxidizes before the carbon has been absorbed. The purified iron is then withdrawn into a furnace, in wh
Periodic Variations of Glaciers.--M. F. A. Forel,of Morges, presented to the first general meeting of the Swiss Society of Natural Science his investigations upon the periodic variations of glaciers. The present remarkable period of glacial retreat began about 1840 in some places, but the Unteraar g