The Union and journal. [volume] (Biddeford, Me.) 1858-1882, 1870-06-03
The Great Submarine Blast.

From the San Francisco Evening Bul
letin of April 23, we CLEAN the following
interesting particulars Of the blowing NJ
of Blossom Rock, the outlines of which
have already been communicated by tele
graph:
Everybody familiar with the character
of our harbor is aware that Blossom Rock
has always been the most dreaded and
dangerous obstruction in it. Little Alca
traz and Sheep Rock are bad. but they are
both ont of the ordinary track of vessels
coming into or going out of tho harbor
and they are both visible. Blossom Rock
however, lies directly in the line of EN-.
trance TO the harbor and near tho route
which the river steamers take, and is O
sunken rock. The engineer of the United
Stares coast survey marked its position
with buoys. which have several times been
swept away. The water ut the Rock o:
low tide was about five feet deep, and the
current ut the point was generally very
strong. Several vessels have struck on 1t,
and it has always been an object of dread
to seamen and navigators. Last year the
Federal Government appropriated $4,000
i'm currency for tho removal of the rock,
and the plans presented by Col. Won
Schmidt were adopted.
The rock had been carefully surveyed
and found to be 1S0 feet long, 90 feet wide
with abrupt sides. and u comparatively
smooth surface. 1t was soft sandstone
like that in Telegraph Hill and Alcatraa
Island. The first work attempted by the
engineer was to ...
REACH TIE ROCK,
| For the accomplishment Of this task a
large, staunch, at-bottomeds scOw was con-
structed. and heavy framework, 81 feet
long, go feet wide and 90 feet high, erect
cd upon it. A double tank or Golfer dam,
about feet square, was built of plank in
the centre Of the craft, running from its
bottom TO the top of the platform. similar
to u fishing smack's we'll room. The space
of two feet was left between the inner and
outer castings of this tank, was filled with
tough clay, packed i'm bagssthus effect
ually shutting of tho water from the out
side. The bottom of the scow was armed
with number of sharp steel-pointed
spikes, arranged In q semicircle near the
outer edges, and after thorough inspection
and overhauling. the whole structure was
towed to the spot by steam-tug. The
craft WAS sunk upon tho comparatively
smooth surface of the rock. anchors were
carried out in different directions, with
chains hove taut on board the vessel, and
200 tons OF rock thrown in. The spikes
penetrated the sandstone on account of
the pressure brought to bear upon them,
and the structure, which rises eight feet
above the surface of the water, was im-
movably set. The water was easily
pumped out of the dam, and the surface
of the rock laid bare for further operation
by the workmen. A circular groove. two
feet deep, was drilled in the rock. into
which an iron turret was hoisted and
timly fixed.
EXCAvATING TIE ROCK.
The surface of the rock having been
exposed, shaft was sunk to the depth of
twelve feet, from which tunnels were run in
different directions, tho ballast worked be-
inc brought to the center shaft, hoistcd In q
tube through the turrett, and discharged
by swinging derrick out in the deep
waiter.
The excavation, when CON- pleted, re-
sembled an immense bake oven. Its di-
mcnsions were rs follows: Extreme
length. 1872 feet, width. GO feet; height ut
the Shaft, l2 feet; the lowest point, 8 feet /;
the thickness of the crust or shell about
10 feet inches, rs near rs could be esti-
mated.
CHARGING TIE BLAST.
It tisa characteristic of human nature
that we delight in the contemplation of
scenes of destruction. Men possesses in u
high degree the animal propensity to des-
troy whatever Obstructs, annoys or endan-
gers him. lie is gratiiied by exhibitions
of force in whatever direction made. He
stands transfixed in the presence Of the
sea, lashed to fury by the gales and the
tornado whirling and sweeping its wrath.
full couriers through The air. The awful
shock of armies. the thunder of navies and
contagration of besieged cities, carry him
to the utmost pitch of animal exaltation.
II was for the qualification of this instinct
that thousands of men, women and chill.
dren came from all parts of the city to-
day to see this famous rock blown to frag.
ments with twcnty-thrco tons OF powder
sunk in its deep caverns. Many expected
to see n column of stones, water and tim.
bcrs thrown two or three hundred feet In.
to the air. and calculated tho chances OF
the entire city being shaken to its founda-
tions. They wished these results might
follow upon the explosion. Certainly
% tons of gunpowdcr Is an immense
charge, and TO explode it under ordinary
circumstances would be like blowing up q
good-sized powder mill. This hugo quan.
tity was contained in large boiler iron
cylinders. Early in the week it was taken
to the rocks on barge and placed In the
chambers. The tanks or cylinders were
connected by wrought-iron pipes, through
which the electric wire was run, so rs tc
explode all Of them simultaneously
When tho powder was all In, the anchors
chains, tools, engine, &C.. were all taken
away, leaving nothing Of value to be In.
volved In the general wreck.
i TIE rIIRoNG or SPECTATORS.
To those who wished to witness the
spectacle from the land. Telegraph Hill
afforded the best and most popular view.
BY 10 NJ. people commenced threading
their way on all sides toward the summit
of the hill. The cars on the lines oi
street railroads leading to North Beach
were crowded with men. women and
children. and by o'clock, p. NJ. Tele'
} graph Hill was black with the multitude.
! North Point and Meiggs Wharf were nj.
so throngcd. and thousands lined the
wharves and docks and shipping. wher'
ever view Of the locality could be OBJ
} tanned. One speculative individual sta.
ltioncd large telescope on the summit O.