and
Lead ; and White Lead (carbonate) Ore. The actual metal is easily
extracted from Galena by heat, which burns away the sulphur, and leaves
the Lead.
"
Massicot " is the raw material which produces Red Lead ; " Litharge" is
the Oxide of Lead which is employed for making the Lead plaster,—of
extensive use in the surgical practice of all hospitals, and a familiar
appliance to cuts and wounds in most households. But, beyond this,
words of grave warning are urgently needed concerning a criminal misuse
to which this " Diachylon " as made and sold for Lead-plaster, is now
not infrequently put when made up into pills at home, as an
abortifacient, in our Midland Counties.
Water,
when absolutely pure, does not act at all upon metallic Lead itself ;
but the oxygen of the surrounding air forms with the metal a hydrated
oxide straightway on reaching it; which oxide is soluble in the water,
and is a cumulative poison ; hence the danger of using Lead cisterns,
with the object of their continuing to contain pure water, is readily
seen. If, however, such water is not absolutely pure, but contains even
a small proportion of lime, (bicarbonate, or sulphate), this will
prevent the water from acting on the Lead, and will make the cistern
comparatively safe. Chronic Lead-poisoning, whether caused insidiously
by the long-continued unsuspected use of water made pernicious by a
small percentage of the metal contained therein, (as met with in the
leaden pipes conveying such water), or whether by daily handling White
Lead in paint, or putty, while pursuing the business of a plumber,
induces what doctors call " Encephalopathy,"—a morbid condition of the
brain, with gradual wasting of the body and limbs. A blue line of
discoloration along the
