82 PARTICULARS OF THE CONSTRUCTION 



thus confined were able to withstand the most violent 

 storm, even without the aid of superincumbent pressure. 

 In this way they proceeded, till beyond the reach of 

 probable danger from the action of trie sea. The cuts 

 at Page 46 and Fig 3, Page 84 shew the places of the 

 wedges at the edges of the stones, and of the trenails 

 through their substance. 



It was before observed, that one great object of Mr. 

 Smeaton was, to have as much as possible of the work 

 done on shore, where no interruption w r ould occur, in 

 order to save the precarious time on the rock. With 

 this view, he had a model of the wrought face of the 

 rock, at the Work Yard at Mill Bay, and each stone 

 was fitted exactly to its place. The stones were 

 shaped at the quarries, but not finished, because their 

 edges would have been liable to damage on the passage. 

 Each stone was finished exactly for its place at the 

 work-yard and laid there ; and the course thus com- 

 pleted. The next course was then completed and fitted 

 on the first. A line was then cut in each stone as it 

 lay in its place, to mark exactly where it fitted. This 

 being done, the lower course was shipped off for the 

 rock, and the other replaced in its position to have the 

 course above it fitted in the same manner. No stone 

 was shipped, until the course above it was completed 

 and ready to serve for fitting the following one, and 

 each stone was prepared with the holes and grooves 

 above stated. 



Besides those holes, a square cavity was sunk into 

 each stone, to correspond with a similar cavity cut in 

 the stone beneath ; so that the two cavities formed a 

 cubic hole of 12 inches diameter. Into these holes were 

 fitted cubes of limestone, by which each course was 

 locked to the one beneath. 



These limestone cubes are seen in Figures 2, 3 

 and 4. 



The first entire circular course was set September 

 8th, 1757 and the third, (being the 9th from the foun- 

 dation) completed in October that year ; when they 

 found it necessary to discontinue working for the season. 



