It has been already said that the Bell Rock rises only a few feet out of the sea at low tide. The foundation of the tower, sunk into the solid rock, was just three feet three inches above low water of the lowest spring-tides, so that the lighthouse may be said with propriety to be founded beneath the waves.

 

One great point that had to be determined at the commencement of the operations was the best method of landing the stones of the building, this being a delicate and difficult process, in consequence of the weight of the stones and their brittle nature, especially in those parts which were worked to a delicate edge or formed into angular points. As the loss of a single stone, too, would stop the progress of the work until another should be prepared at the workyard in Arbroath and sent off to the rock, it may easily be imagined that this matter of the landing was of the utmost importance, and that much 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.

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