Gilpin observer., 1907-08-01
GOLD AND SILVER HAVE coMPE-
TITOR.
(By Capt. James T. Smith in Rocky
Mountain News)

The substitution Of cement for wood
In underground mine workings and in
the construction OF metallurgical
buildings adds fresh importance to this
Colorado product, which has already,
at the hands of experts, acquired the
much-coveted title. THE best in the
world" In proof of this assertion, 1t
may be stated that manufacturers Of
cement in Germany and England have
recently copied the furnaces and other
appliances used at the extensive plant
of the Portland Cemoht Company, To-
Gated at Portland, Fremont county,
this state.
This plant commenced on a very
modest scale in 1901, and when the
plans and specifications for Stratton
hall, on the campus of the Colorado
School Of Mines, were made known to
builders the management of the plant
put up $4,000 bond that 1t could
furnish homemade cement in all re-
spects equal to the imported article,
which the specifications called for.
The offer was accepted by the manage
ment Of the school. Careful tests were
made in the laboratories at Golden,
which are we'll equipped for the pur-
pose, and the promise made on behalf
of the Colorado material was more
than made good. The certificate is
sued to the cement company, together
with the even merits of the article pro-
duced, paved the way for large orders
from Old Mexico, Arizona, New Mex
leo. Utah, Wyoming and California.
In 1906 the plant at Portland pro-
duced about 100000 barrels of ce-
ment. worth at wholesale prices $2.20
per barrel, making the value OF the
years output close to $3.50, 900. About
thirty-three per cent. of this product
was sold in Colorado, for various pur-
poses, the remainder going to the
states and territories mentioned. The
size of the Portland plant is steadily
augmented, there beieng no limit at
present to the raw material at hand.
The proposed ninestory building
now under way at the southeast corner
OF Champa and Seventeenth streets
will be of steel and cement. The large
dams and reservoirs recently planned
in different parts of the state and Of
the newer West will also draw largely
upon the supply of cement. so that the
local output in 1908 will probably
double the output for last year.
In the opinion Of close observers, ce-
ment will be a conte slant with coal
and gold for the first place in Colo
radios mineral output before the end
tion, but the progress of cement In
the country at large places 1t safely in
side the probability lines.
During the past year cement con-
sumption shows a gain of $50 per cent,
compared with 1906. The hydraulic.
portland and Stag cement produced in
the United States has grown from s.
731, ,401 barrels in 1895 to approx
mately 47.50O.000 barrels in 1906. or
444 per cent. In twelve years. A
product of over 60.o00.000 barrels is
predicted for 1907 by the Mining
World Of Chicago.
Reinforced concrete In Office build
ings. bridge foundations, reservoirs
and like structures accounts largely
for the gain In consumption. The ma
terial Is also better understood. and at
all OF the engineering schools the
course in cement has been made i'm
portant. helped by frequent inspection
of work under way.
At the recent session of the Colo
rado-Wyoming Lumber Dealers Asso-
citation in Colorado Springs, A. l.. Tay-
lor of that city read IN interesting and
valuable paper on THE Use and
Abuse of Cement" Some eighty per.
cent. of the American output is now
credited to plants in Pennsylvania.
New York, Ohio, Kansas, Michigan and
Colorado. Portland cement-the kind
made in Colorado-reaches only about
one-half its strength the first month.
and gradually reaches Its ultimate
strength in about three years.
A large proportion of this cement is
made from limestone and shale. 1t Is
manufactured in rotary kiln, which
is a steel cylinder. usually from sew.
etny-five to 120 fet in length and
from six to nine feet in diameter, lined
with first-class fire brick to Withstand
the very high temperature to which
the inner surface Is subjected. The
cylinders used at the Portland works,
this state, are local development. so
superior to those which preceded that
the large plants in England and Ger
many have secured the right to copy
and install them. Gas. crude oil. or
powdered coal may BE used for fuel.
BY the use of forced draft a tempera-
tture of close to 5000 degrees Fahren-
heit Is secured. The test for flneness
in standard portland cement is that
the finished product shall be so fine
that at least ninety per cent. of 1t will
pass through sieve with 10000
meshes to the square inch. Subjected
to this test, the Colorado product
shows ninety.six per cent, or six per
cent. higher than the government
standard. The tensile strength. one
inch section. after one day in air,
shows 400 pounds, whereas the govern
ment requirement IN this test is but
ITS pounds. One part cement and
three parts standard sand. one day in
air and six days In water. give the To-
cal product $50 pounds Of tensile
strength, compared with a government
requirement OF $50 pounds.
Eighteen of the ninety American ce-
ment plants are located west OF the
Mississippi. the gas belt Of Kansas con.