consultation was held in regard to it.
It would seem that engineers, as well as doctors, are apt to differ.
Some suggested that each particular stone should be floated to the
rock, with a cork buoy attached to it; while others proposed an
air-tank, instead of the cork buoy. Others, again, proposed to sail
over the rock at high water in a flat-bottomed vessel, and drop the
stones one after another when over the spot they were intended to
occupy. A few, still more eccentric and daring in their views,
suggested that a huge cofferdam or vessel should be built on shore,
and as much of the lighthouse built in this as would suffice to raise
the building above the level of the highest tides; that then it
should be floated off to its station on the rock, which should be
previously prepared for its reception; that the cofferdam should be
scuttled, and the ponderous mass of masonry, weighing perhaps 1000
tons, allowed to sink at once into its place!
All these plans, however, were rejected by Mr. Stevenson, who
resolved to carry the stones to the rock in boats constructed for the
purpose. These were named praam boats. The stones were therefore cut
in conformity with exactly measured moulds in the workyard at
Arbroath, and conveyed thence in the sloops already mentioned to the
rock, where the vessels were anchored at a distance sufficient to
enable them to clear it in case of drifting. The cargoes were then
unloaded at the moorings, and laid on the decks of the praam boats,
which conveyed them to the rock, where they were laid on small
trucks, run along the temporary rails, to their positions, and built
in at once.
Each stone of this building was treated with as much care and
solicitude as if it were a living creature. After being carefully cut
and curiously formed, and conveyed to the neighbourhood of the rock,
it was hoisted out of the hold and laid on the vessel's deck, when it
was handed over to the landing-master, whose duty it became to
transfer it, by means of a combination of ropes and blocks, to the
deck of the praam boat, and then deliver it at the rock.
As the sea was seldom calm during the building operations, and
frequently in a state of great agitation, lowering the stones on the
decks of the praam boats was a difficult matter.
In the act of working the apparatus, one man was placed at each of
the guy-tackles. This man assisted also at the purchase-tackles for
raising the stones; and one of the ablest and m
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