On the 4th of November fifty workmen commenced digging, in the
very center of the enclosed space on the summit of Stones Hill,
a circular hole sixty feet in diameter. The pickaxe first
struck upon a kind of black earth, six inches in thickness,
which was speedily disposed of. To this earth succeeded two
feet of fine sand, which was carefully laid aside as being
valuable for serving the casting of the inner mould. After the
sand appeared some compact white clay, resembling the chalk of
Great Britain, which extended down to a depth of four feet.
Then the iron of the picks struck upon the hard bed of the soil;
a kind of rock formed of petrified shells, very dry, very solid,
and which the picks could with difficulty penetrate. At this
point the excavation exhibited a depth of six and a half feet
and the work of the masonry was begun.
At the bottom of the excavation they constructed a wheel of oak,
a kind of circle strongly bolted together, and of immense strength.
The center of this wooden disc was hollowed out to a diameter
equal to the exterior diameter of the Columbiad. Upon this wheel
rested the first layers of the masonry, the stones of which were
bound together by hydraulic cement, with irresistible tenacity.
The workmen, after laying the stones from the circumference to
the center, were thus enclosed within a kind of well twenty-one
feet in diameter. When this work was accomplished, the miners
resumed their picks and cut away the rock from underneath the wheel
itself, taking care to support it as they advanced upon blocks of
great thickness. At every two feet which the hole gained in depth
they successively withdrew the blocks. The wheel then sank little
by little, and with it the massive ring of masonry, on the upper
bed of which the masons labored incessantly, always reserving some
vent holes to permit the escape of gas during the operation of
the casting.
This kind of work required on the part of the workmen extreme
nicety and minute attention. More than one, in digging
underneath the wheel, was dangerously injured by the splinters
of stone. But their ardor never relaxed, night or day. By day
they worked under the rays of the scorching sun; by night, under
the gleam of the electric light. The sounds of the picks against
the rock, the bursting of mines, the grinding of the machines,
the wreaths of smoke scattered through the air, traced around
Stones Hill a circle of terror which the herds of buffaloes and
the war parties of the Seminoles never ventured to pass.
Nevertheless, the works advanced regularly, as the steam-cranes
actively removed the rubbish. Of unexpected obstacles there was
little account; and with regard to foreseen difficulties, they
were speedily disposed of.
At the expiration of the first month the well had attained the
depth assigned for that lapse of time, namely, 112 feet. This depth
was doubled in December, and trebled in January.
During the month of February the workmen had to contend with a
sheet of water which made its way right across the outer soil.
It became necessary to employ very powerful pumps and
compressed-air engines to drain it off, so as to close up the
orifice from whence it issued; just as one stops a leak on
board ship. They at last succeeded in getting the upper hand of
these untoward streams; only, in consequence of the loosening of
the soil, the wheel partly gave way, and a slight partial
settlement ensued. This accident cost the life of several workmen.
No fresh occurrence thenceforward arrested the progress of the
operation; and on the tenth of June, twenty days before the
expiration of the period fixed by Barbicane, the well, lined
throughout with its facing of stone, had attained the depth of
900 feet. At the bottom the masonry rested upon a massive block
measuring thirty feet in thickness, while on the upper portion
it was level with the surrounding soil.
President Barbicane and the members of the Gun Club warmly
congratulated their engineer Murchison; the cyclopean work had
been accomplished with extraordinary rapidity.
During these eight months Barbicane never quitted Stones Hill