An Account of the Bell Rock Light-House / Including the Details of the Erection and Peculiar Structure of That Edifice; to Which Is Prefixed a Historical View of the Institution and Progress of the Northern Light-Houses

by Robert Stevenson

This morning several casks of pozzolano, lime and sand were landed, to make mortar, in order to build round the lower edges of the foundation-pit. This being something like an approximation to the long wished-for commencement of building the Light-house, the artificers thought the opportunity too good to pass over in silence, and the casks were accordingly landed under a salute of three hearty cheers. At half past 6 P. M. the boats again landed upon the rock, but, even when the tide was at the lowest, the water stood to the depth of 18 inches upon the site of the building, and no work was done. This was rather a relief to the smiths, who having no irons to sharp, got rapidly forward with the necessary fixtures for the railways.

Thursday, 23d.

Small ruble walls built instead of cofferdam.

The weather continued to be extremely mild, and the winds were generally from the eastward and southward, accompanied with thick and hazy weather, which, in communicating with the rock, was not only irksome but even dangerous. At 7 o’clock this morning, the tide proving more favourable, the artificers began to work. At 9 the rock was again overflowed, and the boats returned to the Tender after two hours’ work. Part of the operations of this morning’s tide consisted in building up the crevices and inequalities of the rock round the margin of the foundation, with pozzolano mortar, and the chips produced from the excavation, with a view to dam out the water. These little walls varied from six inches to eighteen inches in height; a small sluice or aperture being formed in one of them by which the water, during ebb-tide, was allowed to drain off.

It formed part of the writer’s original design, as formerly noticed, to erect a cast-iron coffer-dam of about five feet in height, round the site of the building; but the surface of the rock was so irregular, that the difficulty of tightening it, and also of emptying the contained water, so as to get the benefit of it during ebb-tide, would have been so great, that, taking these circumstances into account, together, with the loss of time which would attend the erection of such a preparatory work, the idea of a coffer-dam was laid aside, soon after entering upon the actual execution of the work.

Inconveniencies of foggy weather.

The boats landed this evening, when the artificers had again two hours’ work. The weather still continuing very thick and foggy, more difficulty was experienced in getting on board of the vessels to-night, than had occurred on any previous occasion, owing to a light breeze of wind which carried the sound of the bell, and the other signals, made on board of the vessels, away from the Rock. Having, fortunately, made out the position of the sloop Smeaton, at the N.E. buoy,—to which we were much assisted by the barking of the ship’s dog, we parted with the Smeaton’s boat, when the boats of the Tender took a fresh departure for that vessel, which lay about half a mile to the south-westward. Yet such is the very deceiving state of the tides, that although there was a small binnacle and compass in the landing-master’s boat, we had, nevertheless, passed the Sir Joseph a good way, when, fortunately, one of the sailors catched the sound of a blowing-horn. The only fire-arms on board, were a pair of swivels of one inch caliber; but it is quite surprising how much the sound is lost in foggy weather, as the report was heard but at a very short distance. The sound, from the explosion of gunpowder, is so instantaneous, that the effect of the small guns was not so good as either the blowing of a horn, or the tolling of a bell, which afforded a more constant and steady direction for the pilot. It may here be noticed, that larger guns would have answered better, but these must have induced the keeping of a greater stock of gunpowder, which, in a service of this kind, might have been attended with risk. A better signal would have been a bugle-horn, the tremulous sound of which produces a more powerful effect in fog, than the less sonorous and more sudden report of ordnance.

Friday, 24th.

The artificers landed to-day, both with the morning and evening tides. During the first, they had two hours and three-quarters, and in the latter, two hours and a quarter, making together five hours work; the weather still continuing thick and foggy, with the wind at south-east.

Saturday, 25th.