332 KANSAS CITY REVIEW OF SCIENCE. 
but in general resembling a breccia of sharp, angular pieces of flint, closely- 
cemented by crystallized blende with occasional masses of bright, crystalhzed 
galena. With the exception of these bars and occasional pillars to support 
the roof, the whole body is blasted out. Draining is difficult, and rock drifts 
are sometimes necessary to unwater the ore. Dr. Schmidt considers a 
secondarily deposited quartzite to be the cementing material between the chert 
and the zinc blende in the very similar deposits found at Oronogo; but this is 
certainly not the case in the best mines at Webb City nor at Sherwood, and zinc- 
buyers soon learn to detect the difference. Where the cementing material is 
pure blende, the blende breaks freely from the chert, and can be almost entirely 
cleaned by crushing and jigging; where the cementing material is quartzite, or 
black sand, as the miners call it, crushing is difficult, and a satisfactory separation 
is impossible. The mines spread over about a section of land, 640 acres. Their 
weekly output is about 700 tons. The method of working them is as follows : 
When a good prospect is discovered in new ground, the land around it is leased 
from its original owners, on royalties ranging from 10 to 25 percent, by a number 
of individuals, who organize various mining, or as they would more properly be 
called, land companies. These companies have the land divided up into lots 200 
feet square, and a plat of it made; select certain lots for themselves, and throw 
the others open to miners. They usually start a shaft on one of their own lots, 
and put in a pump. If the indications continue good, many of the lots, particu- 
larly those near the pump-shaft, are quickly taken up by parties of miners, who 
sink shafts upon them, timber the ground, put up hoisting contrivances, furnish 
all supplies, and bear all expenses. 
When ore is struck, it is drifted on and followed in all directions up to the 
boundaries of the lot in question. The ore is raised to the surface and crushed 
and washed by the miners, and is sold to one of the zinc or mineral buyers. It 
is weighed over the company's scales, and paid for to the company, which deducts 
a royalty of 25 per cent on zinc-blende and 50 per cent on " mineral " (galena); 
and if it has pumps running, a pump rent of $1 a ton on zinc ore and $2 on 1,000 
pounds of galena ; and pays over the balance to the miner. The royalties, of 
course, vary with circumstances, but the above are general. The holders of lots 
hire other labor to do the mining at from $1 to $1.50 a day; and usually put up 
crushing and washing machinery on their lots. Very often the same parties con- 
trol two or three adjoining lots or fractions of lots, and sometimes neighbors go 
into partnership. Most companies do not allow ores to be taken from the lots 
on which they are mined until they have been cleaned and have paid royalty. 
The machinery is usually of the simplest description — a farm or small stationary 
engine, covered by a shed of rough boards, a small-sized Blake's breaker, set 
over a pair of rolls, and a horse whim or whip. The jigs are ordinary hand-jigs, 
with an overhead breakstafif, working a sieve 2x3^ feet up and down in a box 
of water. The jigging is usually done by contract, and is paid for by the ton of 
cleaned ore. It is common to see from ten to twenty jigs grouped together under 
a shed of poles, covered with branches of trees or rough boards. The ore as 
