Grant County herald. [volume] (Lancaster, Wis.) 1850-1968, 1886-08-12
huIOHldH.
Laurentian.

luo bdiehd anu lrentOH limestone
are the strata which most interest us in
this article, as they are the lead bearing
strata. During this period, which is
called the the Lower Silurian age, the
waters which covered this section was
rich in lead and other minerals, as zinc,
copper and metals can be dissolved and
held in solution by treating with va
rious acids. Different metals require
different solvents, but the metal can al
ways be precipitated by adding some
other chemical. For instance, a solu-
ton of lead is precipitated by sulphur
eted hydrogen into a black precipitate
of sulphuret of lead. 1t combines with
iodine. forming iodide of lead. Ii
forms five oxides when treated with
oxygen. In nature it is found as sui.
phuret, an oxide, sulphate, phosphate,
carbonate, arseniate, molybdate and
tungstate. Many forms of animal life
existed during this period and contrib
uted part of this sulphureted hydrogen
which, combining with the lead in solu.
ton, precipltated sulphuret of lead,
galenite or lead ore; the terms are
synonymous. The precipitated lead ac-
cumulated in the cracks and assures of
the Galena and Trenton limestone,
where the water circulated, forming
the leads, veins and pockets. which the
miner, thousands of years afterward,
found and worked.
Lead is formed IN natural state in
all the forms above enumerated but
galenite or sulphuret of lead is the only
form from which the lead of commerce
is extracted. The metal is one of the
softest and least tenacious, blueish in
color, quite brilliant when fresh, but
quickly furnished when exposed to the
air. When exposed to the combined
action of air and moisture its oxidation
is rapid; whitish coating forms, whic b
is soluble in pure water and sometimes
causes fatal poisoning where soft water
is used out of leaden reservoirs; but if a
small amount of sulphur or lime is held
In solution in the water these form with
the oxide of lead into white crust
which is insoluble by water and which
also protects the lead from further oxi-
dation, for this reason hard water car
ried through lead pipes is harmless.
Lead is used for great variety of pur-
poses and in many chemical prepara-
tons. Some of the principal uses of
the pure metal are in pipes, which are
made by forcing lead through dies;
shot, which are made by dropping the
melted lead into water from sufficient
hight to allow it to become cool enough
to be solid, and afterward separating
the different sizes by means of screens
placed slanting on frame; the holes in
the top screen allow all to pass through
except the largest size. The next has
holes size smaller and so on on to the
smallest. The shot that are stopped by
each screen roll to troughs at the lowest
ends and are conveyed TO receptacles,
each size snot in different box. They
are then polished with black lead and
are ready to be shipped.
Bullets for rifles are either swaged
when made on large scale, or nodded
when made in small amounts. A small
amount of tin is sometimes added Lead
IN sheet is used in making cisterns,
sulphuric acid chambers and for great
many other purposes. Lead is liza
times as heavy as water. and melts at
6120 I. 1t shrinks on cooling, making
it unit for fine castings, but by adding
one part of anthony to three parts of
lead an alloy is made which expands as
it becomes solid. making an accurate
casting. Printing types are made of
this alloy. Pewter is an alloy of lead.
tin, bismuth and anthony Solder is
an alloy of lead and tin. 1t meits more
easily than either tin or lead and fastens
sheets of either metal together without
melting them.
Acetate of lead (sugar of lead) is
made by dissolving litharge (oxide of
lead) with acetic acid (vinegar) and is
used for various purposes, principally
dyeing.
Carbonate of lead white lead) is the