New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1900-08-12
AMERICAN PORTLAND CEMENT
RAPID GROWTH IN ITS PRODUCTION WITH
IN THE LAST FEW YEARS.


A number of observation-disclosures them the al
legged pecuniary interest of Tammany ofnclais IN
the industry-have recently called attention to the
production of hydraulic cements in this country.
A hydraulic cement. it may be necessary to explain
to some readers Is one which has the ability 10 set
or harden under water. 1t is extensively employed
In the construction of bridge piers, docks, the
foundations of buildings and increasing variety
of other work. Cement is rarely used pure and 1t
is generally mixed with sand and gravel the COM
pound being known as concrete. If the cement Is
properly chosen and the proportions of the SAND
apd Gravel are not too large concrete will prove
as hard and serviceable granite, besides being
cheaper.
The lime used in the preparation of mortar for
ordinary buildings is derived from a limestone
containing only little impurity, say. from TO
per cent The rest is carbonate of lime Such
a stone, being burned, Yields product which
when water IS poured upon 1t, is reduced 10 a
powder with the evolution of much heat This
operation is called shaking" Now, this kind of
limestone will not make a good hydraulic cement
without the addition of other substances. The stone
originally used for making cement at Portland
England, contained only from rs to so per cent of
carbonate Of lime and from 20 to % per cent OF
CLAW The clay in turn, was mixture, and was
composed of about one and half or two parts OF
silica to of alumina. When this kind of stone
was burned the silica and alumina combined so
thoroughly with the lime that none of the latter
was left free TO slake. Any cement made arti-
hciaIly after that formula in Europe or America
is Portland cement
One which is nearly the same, but contains GER
tain percentage Of magneSia. is called RosendaIe
cement. It will not produce good results as the
other kind But for many classes of work its
cheapness gives 1t the preference
land Cement Manufacture in America is the sub
Ject of elaborate article in last week
Engineering News Although England was the
birthplace OF the industry, she no longer has a
monopoly Of ii. Her annual production Is now be-
tween 100000 and 100000 barrels that of France
barely 100000 and Germanys output from 100000
to 100000. Moreover the quality of the German
product is so excellent, and its makers have urged
its merits on the attention of American engineers
vigorously, that large quantities of the article
have been imported to this country.
A diagram in THE Engineering News striklngly
illustrates the growth Of the business in America
since 1888 In that the consumption was about
100000 barrels, and nearly that amount was Inn
poTted-that is TO say the domestic production was
small. In 1891 Americans consumed nearly 3.5O00O6
barrels and produced less than 100000, about one
seventh of the consumption Three four years
later, however, the American industry Spurted BY
1897 our production exceeded Importation, tie
former nearly amounting 100000 barrels and the
latter falling TO vicinity of 20)0000 barrels Last
and imported 100000 barrels But while the output
of domestic cement has rapidly increased during
the last few years, the consumption has also de-
Veloped enormously, that The Engineering
News estimates the mills of the country will not
catch up with the home demand for ten or twelve
| years TO
supply Of raw material. but has adopted methods
| and apparatus which enable her to make cement
more rapidly than the foreigners and in the quality
Of this article the United States already leads all
| other countries.