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

The hewing or cutting of the several courses, forming the void of the Light-house, was also in great forwardness in the work-yard at Arbroath; and by the latter end of the month of April, the Forty-fourth course, forming part of the store-room, shewn in the section of [Plate XVI.], was laid on the platform, and ready for shipping to the Rock. The burning and pounding of the Aberthaw lime, and the preparation of other materials, were also going on.

1810, April.

Landing on the Rock precarious in Winter.

The season, though now advanced to the month of April, was still boisterous. The day, however, was getting long, and the influence of the sun began to be felt in checking the frosts, which often stopped both the quarrying operations and the stone-cutters. The lengthening of the day, as well as moderate weather, was a great regulating circumstance in the Bell Rock works; for, during the winter months, only one low-water tide occurred with day-light; and, indeed, in the depth of winter, there may be said to be no very favourable opportunity of landing on the Rock, as low-water at new and full moon happens here about 8 o’clock, which renders the chance of landing extremely uncertain and precarious.

Retrospective view of the works. Mylnefield Quarry.

Previously to entering upon the operations of the season 1810, it may be proper, in this place, to take a retrospective view of the various departments of the work. The granite courses of the Bell Rock Light-house having been completed, for a considerable time, it was only the sandstone quarries that were to be attended to. As formerly noticed, the stone of Mylnefield, like that of most quarries which lie in strata or alternate beds, is liable to split and become useless, from the effects of frost, owing to the natural sap or moisture which they contain. Water, being unlike other bodies which follow the general law of contracting in volume with a reduction of temperature, is found, on the contrary, to encrease in bulk at the moment of congelation, producing the most surprising effects in rending rocks, even with an explosive force. In sandstone quarries, therefore, the work is usually suspended during the months of December, January, February and March, when the frost happens to be intense, as was the case in the winter of 1809–1810, when the thermometer occasionally fell so low as the 17th degree of Fahrenheit. Notwithstanding every precaution in the work-yard at Arbroath, by covering the quarried materials with straw and brushwood, many excellent and valuable stones were lost by the intenseness of the frost. Such, however, was the desire of getting early forward with the work, in order to insure the completion of the building operations in the favourable part of the season, that the writer took the earliest measures for getting an additional supply of stones from Mylnefield; and, by the beginning of the month of April, the Smeaton and Patriot, together with the hired sloop Alexander, were loaded and sent to Arbroath.

Craigleith Quarry.

From this description of the nature of the stone of Mylnefield, it became necessary, for the furtherance of the upper parts of the Light-house during the winter months, that they should be prepared of stone which would admit of being worked without much risk of injury during frosty weather. For the cornice of the building, and the parapet of the light-room, the writer, therefore, made choice of the Liver-rock of the Craigleith Quarry, well known for its durability and beauty, and for its property of not being liable to be affected by frost. By this means also, the iron-work or frame of the Light-room might be fitted to the masonry on the spot where it was to be prepared, which would thereby lessen the actual work upon the Rock. Another advantage attending this arrangement, was the opportunity it afforded of making practical trial of the Balance-crane, with which the masonry of the ensuing season was to be built, as it had been found necessary to make several alterations on its construction.

State of the Works at Edinburgh.

The use of a piece of vacant ground was accordingly got at Greenside, contiguous to the author’s house, in Edinburgh, where a number of masons were employed, at the sight of Mr Peter Logan, foreman builder. A very considerable difficulty was, however, experienced in procuring so many principal stones of the liver-rock, of the description and dimensions necessary for the cornice and balcony; the stones of which also formed the Light-room floor in one length, as will be understood by examining Plates [XIII.] and [XVI.] But, as these works commenced at Edinburgh in the latter end of October 1809, they were completed early in the month of March 1810, and the whole of this critical and difficult part of the building was then ready for shipping to the Bell Rock. The several compartments of the Light-room were now also in progress. The sheets of silver-plated copper for the reflectors having been ordered from Messrs Boulton and Watt,—the glass from the British Plate-Glass Company,—the cast-iron sash-frames from Mr John Patterson of the Edinburgh Foundery,—while the construction of the reflectors and reflecting-apparatus, together with the framing of the whole Light-room and its appurtenances, were executed under the immediate directions of Mr Thomas Smith, the writer’s predecessor, who had now retired from the more active duties of engineer to the Light-house Board.