FOOTNOTES:
[4] This was the Derwentwater Estate which was forfeited in the year 1715, and its revenues applied by Parliament towards the funds of Greenwich Hospital. It consists of mines of lead, containing much silver, as well as lands. It required careful management, and the knowledge of mining details to make it profitable. Smeaton contrived more efficient machines and better modes of working the mines and managing the estate.
Chapter V.
THE EDDYSTONE AS A TYPE OF ENGLISH LIGHTHOUSES.
A Stone Lighthouse proposed—Smeaton’s first Visit to the Rock—Operations of the First Season—Second Season—Structure of the Foundation—Ingenious Mode of securing the Stones—Third Season—State of the Work—Progress and Description of the Work—Accidents to the Engineer—Proposal to exhibit a Light before the completion of the Building refused—Fourth Season—Completion of the Work—Appearance of the Lighthouse during a Storm—Situation of the Light-keepers.
To return to the history of the Eddystone Lighthouse. When the proposal relating to the rebuilding of this edifice was made to Smeaton, and when he had duly weighed the subject in his own mind, he delivered his decided opinion that the building ought to be constructed entirely of stone. Some opposition was at first raised against this idea, but the proprietors were at length so well satisfied with the plans submitted to their inspection, and with the plain, straightforward reasoning of Smeaton on the matter, that they left the whole affair in his hands. Their chief objection had arisen from the opinion, supported by that of the best judges, that the safety and continuance of Rudyerd’s lighthouse during so many years, had in a great measure depended on the elasticity of the materials of which it was composed, which enabled it to give way to the shocks of the sea. Indeed it was affirmed, that in violent storms the motion of that wooden edifice was so great that trenchers and other articles were thrown from the shelves in the upper rooms. Smeaton answered to this, that the great agitation of the late building arose from its want of weight, as well as want of strength; that the edifice he had in view would be much heavier and much stronger, so that the building would not give way to the sea, but the sea would give way to the building.
In the spring of 1756 Smeaton first visited and examined the Eddystone rock, proving, as his predecessors had done, the extreme difficulty of gaining a landing, or of remaining long enough on the rock to carry on his observations. These difficulties suggested to him the important and valuable expedient of keeping a vessel fixed within a quarter of a mile of the rock, which should be capable of lodging the workmen and their tools, and thus enable them to take immediate advantage of any favourable opportunity of putting out their boat and conveying materials at once to the Eddystone, instead of having to take the voyage from Plymouth on each occasion.
The first actual work done on the rock was in August, 1756. Two companies of workmen were employed, each remaining at the work a week, that every opportunity might be made the most of, and the men relieved by visits to the shore. A sloop, a large yawl with sails and oars, and a boat, were employed to expedite the work. The sloop formed the lodging for the company working at the rock, and was anchored at a short distance from it. The sloop was afterwards replaced by a larger store vessel, called the Neptune Buss. The weather from the 27th of August to the 14th of September happened to be favourable to the work, so that the companies were employed on it at every tide. After this, unsettled weather began to prevail, so that Smeaton was obliged to be satisfied with the progress already made, which consisted in the mere preparation of the House-rock for the intended edifice, by cutting two new steps in the lowest part of the sloping side of the rock, and forming anew the five steps which remained of the efforts of Rudyerd. Dove-tailed recesses were also cut in all these steps for the reception of the stone-work. The remaining part of the autumn was spent in expediting necessary work on shore, such as completing the work-yard with its machinery and conveniences, and then preparing the granite and Portland stone, of which the lighthouse was to be made. The desirability of doing as much of the work as possible on shore, became more and more apparent, as experience showed the dangers and accidents likely to occur at the rock. During this winter Smeaton began seriously to consider the great importance to his work, of getting the most perfect cement possible, to resist the extreme violence of the sea. He found that nothing of the resinous or oily kind would answer, as it was impossible to get a dry surface at the rock. He therefore went through a complete set of experiments on cements with a view to produce one which would, in despite of water almost continually driven against it with every degree of violence, become so firm in its consistence and adhesion to the stone, that it should compose one even regular surface with the stone, without needing hoops of iron or copper to surround the horizontal joints. In this endeavour he considered himself at length completely successful.
At the beginning of June, 1757, Smeaton renewed his work at the Eddystone rock. The first proceedings were to fix some timbers to the east side of the rock merely as a defence to the boats, which were frequently damaged by running against the sharp edges; and also to erect shears, windlass, &c. The first stone was laid in its place on the 12th of June. This stone weighed two tons and a quarter, though the ordinary weight of the stones did not exceed one ton each. The first course consisting of four stones was finished during the next day. By Smeaton’s plan the stones were most ingeniously dove-tailed together and into the rock, so that when once fixed, it was impossible for one stone to be separated from the rest. The second course of stones was not completed until the 30th of the same month; several accidents having occurred to hinder the progress of the work; yet Smeaton was in no wise disheartened, for in establishing these two courses he considered the most difficult and arduous part of the work to be already accomplished, since these courses brought him up to the same level where his predecessor Mr. Rudyerd had begun. On the 11th of July the third course, consisting of twenty-five pieces, was completed, and on the 31st the fourth course of twenty-three pieces. The fifth course was closed in on the 5th of August. When the sixth course was completed, which was on the 11th of that month, Smeaton had the satisfaction to find that the sea did not now invariably wash over every part of their work at each tide, which had always hitherto been the case in the course of laying the previous courses. The greatest difficulties were now considered to be successfully surmounted, as each succeeding course gave them more time and more room, and they had brought their work to a level with the highest part of the rock.