The daily exchange. [volume] (Baltimore, Md.) 1858-1861, 1860-06-14

REFER 10 the column OF white marble from the Con
molly quarries, Cockeysville, the forerunner Of
hundred of the same size to be supplied under
contract for the porticos of the two new wings of
the Capitol at Washington. This column is twenty
six feet long, of an average diameter of more than
three feet, and weighs upwards of twenty three
tons. All the rest will be of the same size and
quality. The material of which this shaft is com
posed is very beautiful, being a compact close
grained, greyish-whte, magnetism lime stone,
easily wrought, but of immense strength and
| lidity. the quarry from which it was taken lies
a short mile from Cockeysville, on the land of
William Bosley, Esq, to which the Messrs. Con
molly have constructed branch rail track, which
| allows the locomotives of the Northern Central
Railway to back directly up to the works. At the
! same point they nave an extensive marble mill,
| driven by the power of the Beaycr-dam run, at
which they manufacture slabs, tomb stones,
asher, ntels, door-steps, and all the thou
sand and articles for which at the pres
ent day, marble is called into requisiton. This
enables them to prosecute the business of
quarrying such gigantic monoiths as those they
are now delivering, with great economy and profit
-nasmuch as the accidental spelling of a column
will thereby be prevented from becoming dead
loss, since it will then only "bring grist to the
mill" 1t will readily be imagined that job of
such extent must require corresponding amount
of the raw material as well as great facilities for
prosecuting the operations required in taking it
out of the ground. An inspection of the quarry
will satisfy all doubts that score. The rock
underes many square miles in the vicinity, crop
ping out in various places, and would furnish abun-
dant supplies for the reconstruction of the Pyra-
mds Where the Connolly quarry is opened, it lies
in nearly horizontal strata in rather level field
covered by some ten or fifteen feet of clay, which
has to be stripped off. comparatively smooth
and level surface of rock is thus exposed and the
first labor of the quarryman is to obtain breast.
This is effected by blasting down to the required
depth, and there then remains no difficulty, what
ever may be the labor, in taking out blocks of al
most any size or shape. To accomplish this the
surface of the rock is first lined off in the proper
direction. Upon this line, as many men as can
conveniently stand, set to work with drills to
| cut holes perpendcularIy down to the required
| depth. These holes are increased in number until
they stand about two inches apart all along the
| line, when the nterstices between them are re-
moved by toothed drill of peculiar construction,
| held in the hand, and worked like the ordinary
churn drill. 1t will be perceived that the block
| is now free three sides, and remains attached
only at the bottom. To separate it here
10 hol ncCSsSdlS W repeat Tue process Just Qe-
scribed of cutting a channel, sheer along to meet
the just chiseled out. 1t is now only required to
drill comparatively few holes horizon tally along
the line of proposed detachment, into which wedges
are driven. and the separation is readily effected
by splitting. When these columns are thus severed
| from the living rock, they are roughly dressed
| down to something like their final dimensions in
order to reduce their weight as much as possible.
They then lifted Inv ,f
| upon railway trucks-the locomotive backs up and
tackles on, and the proprietors heartily wish them
bon coydge to Washington, anticipating the moment
when the one hundredth passenger shall reach
the same destination, and Uncle Sam shall fork
over hundred and fifty thousand dollars,
which he has promised when that event shall hap
pen.
Among the many advantages possessed by the
site of Baltimore, none is conspicuous than the
wealth OF building materials of the choicest quality
lying in profusion all about u.s. In digging cellars
in some places, remove the best brick CLAY in
the world; in others, the finest sand; the very
limits of the city are quarries of gneiss and horn
blende which cannot be surpassed, while at the
distance of some dozen miles, reduced to nothing al
most by railways passing through them, we have
inexhaustibe deposits of MARBLE limestone, and
granite of the very best description. AS if these
natural advantages not enough, we have more
than one foundry where iron is made to assume all
the shapes to which modern architecture devotes it,
of excellence and cheapness at least equal to
those Of any other city in the country
Being by railway, canal and river connections, es
sentally the depot of the Susquehanna valley, we
have lumber the best terms of the seaboard
Under such circumstances it gives sincere regret
| to find Northern builder obtaining the contract
for the U. S. Court House, and with marble at
doors which be furnished at about the same
| cost, to know that this building will probably be
| constructed Of Northern granite. We suppose
| that circumstances come too late, but we
shall not on that account be hindered from say
| ing that we extremely sorry that any material
| should have been thought of for this work but
| Baltimore county marble.