Page:A Book of the West (vol. 2).djvu/149

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ARSENIC MANUFACTURE
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coppice and jutting crags, the most beautiful portion being at Morwell.

There are several arsenic works in this district. The mundic (mispickel-arsenic), which was formerly cast aside from the copper mines as worthless, is calcined.

The works consist in the crushing of the rock, it being chewed up by machinery; then the broken stone is gone over by girls, who in an inclined position select that which is profitable, and "cast aside the stone without mundic in it. This is then ground and washed, and finally the ground mundic is burnt in large revolving cylinders.

The fumes given off in calcining are condensed in chambers for the purpose, and deposited in a snow- white powder. The arsenic is a heavy substance with a sweetish taste, and is soluble in water. In the process of calcining a large amount of sulphurous acid is given off—a pungent, suffocating gas—and this, escaping through the stack, is so destructive to trees and grass, that it blights the region immediately surrounding. When, however, a stack is of sufficient height the amount of damage done to herbage is greatly reduced, as at Greenhill, where there is a healthy plantation within two hundred yards of the stack.

When the workmen have to scrape out the receivers or condensers, the utmost precaution has to be taken against inhaling the dust of arsenic. The men engaged wear a protection over the mouth and nostrils, which consists in first covering the nostrils with lint, and then tying a folded handkerchief out-