, 1888-01-08

EAP or MICHIGAN COPPER nRoIoN.
Tho Calumet aud Hsola mlno has bosn
worked 30 extensively since 1910 that tho
underground timberinE included many mil
lion fost Of beams and supports. To those
not familiar with mining ID IL only necessary
TO say that the interior OF a largo mino must
be divided into "hoorG" or 'lsvels,"
and ~ fast ~ the ore and waste
material arc removed each floor must DO
laid with stout cross tiInborS supported
by the strongest uprishts, to furnish a work
Ing basis 10 talks cut ore above IL and support
whatever mass OF rock and earth is between
the top of the ore md the surface. Tho
proper arrangement OF thls timbering Ia enc
OF tho most technical jobs In a mine, and
fearful disasters occur when II II badly done.
When bsrnod out, As in shis mine, the entire
rod falls In The ds6riI must thsa be cleaned
out md all the timberinG reset. Many can
turiss ago the mines on the southern more OF
Lake Superior ware worked by that mysterl-
Gus people 10 uhon scholars have given the
vague name Of ''meund builders" They
worked by very rudo processes, such as Stone
hammers and wedgss; bu, shay used tho COP
per 70 make axes, and IL is eo~njsctured shat
they had shs art OF hardening ID The whites
began regular workings there In 1s45, but
advanced 30 slowly that al tho beginning of
the WAr the snstrs output had not amounted
to 25,oeo hons. Bus the mighty energies
evolved in the strife soon found n Geld in in
duutrial Developments, and in = few years the
product OF the Michigan copper mines reached
l2,o0o tons annually. Suppressed for n time
by the pR.is Of 1928, the product again in
cresrod rapidly aid nav minss being opened
elsewhere the price declined greatly. Down
to 1880 tia United States imPorsOd some cop
per; since that date 10 has exported enormous
quantities. Tbs copper of Michigan Is almost
..A.lN.. 4I-.kt-.N Nl.A a.. a .,-.la. -. Al
ore directly into pure copper, and masses of
the pure metal Weighing many tons arc mot
with. II Is found in ths bedded trAppsan
rocks with intsrstrRtifsd sandstspSB and
c~onSlomsratSS. Ths smaller mASsss or
grains, which still furnish tho lsrgost
amount, are found Ia a soft AmysdRloidl
trap, locally known rs rho lash beds"
There il also = copper rsEioA OF HroNt sxtont
and Supposed richness in tbs adjacent SOC
lions q Virginia, North CArehnA And Ten
neskes, with spurs running into Georgia,
and smaller niRss In Maryland, Nevada,
Vermont and sthsr places, all Of which would
DO proatably worked with a small advance
in the price. But the great hope of far wost-
orn miners is ia the development of ooppsr
mines in Montana which are claimed to DO
very rich and iEsNhRustibls, II the Calumet
and hsclR mine should have TO be closed for
one ysar-as Is quite probable, all Sho tim
berisE in the mine being burnsd-anplo tino
would be given to develop Tho Montana
mines on a large scale. II IL claimed
that 5000 tons yearly can easily be produced
thsro, nnd 1900 or mere IN Arizona; aAd ~
the United States has lately exported some
1900 tons yearly, is world c~ertsialy soem
that tins closing OF the largest Minis In Eiohi-
gan conld make no spprseIRhls diHorssoo In
the price. Chill ia alIs Increasing her output
Il IL trus tho ehsspsnlnI Of copper hns greatly
inC-c..si i- uses, but ths supply has in
creased much faster, 70 We may rely upon
permanent Low prices. TIE worlds yearly
supply ei copper has boon estimated As fol-
lowt: $500 tons in 1850, 81 coo tons in 1s4o,
5000 tos5 IN 1889, &c 200 tens in 1870, and
over s0,cS tors since 1880.
Tbs worlds yield Of copper sold at an
EyerE5. e $500 = ton for many Year,, then
tie long dsclins set in and continued with
scarcely q cEsnEo till during the last
season il sold in New York for ten cents
g posnd. A rise came al last, purely spscu-