OF THE EDDYSTONE LIGHTHOUSE. 83 



On the 14th May, 1758, Mr. Smeaton went out 

 again, and found that the winter's storms had not 

 damaged his work in the smallest degree ; and that the 

 mortar was become as hard as the stone itself. 



In that year they got up to the 29th course and laid 

 the first floor. 



From the ?th to the 14th course, the building was 

 entirely solid, and from the 14th to the 24th continued 

 so, except a circular staircase in the centre. Thus far 

 it was fastened as has been already described. 



But having now reached 27 feet above spring tide 

 high water mark, Mr. Smeaton considered the work 

 out of danger from the stroke of the Sea, and began to 

 form the rooms : in which the mode of fastening the 

 stones was as follows. At the bottom of each stone a 

 cavity was made for a marble block, as before, and at 

 each end was cut an angular groove, such, that when 

 two stones were fitted together, they formed a rhombic 

 or diamond shaped hole, 5 inches long, 2 J inches wide 

 and about 18 inches deep. Fig. 5. Into this a slip of Pur- 

 bee was fitted. A hole was then sunk in the top of each, 

 with a jumper, to take the ends of an iron cramp ; for 

 as they were now got out of the reach of the sea in 

 moderate weather, they could afford a little more time 

 in their operations. All these were completely fitted 

 at the work yard. When the stone arrived on the 

 rock ; the blocks of marble were first set in their places 

 with a little mortar, then the mortar was spread on the 

 bed of one of the stones, which was set in its place: 

 the next was then built in beside it, with mortar, as in 

 common masonry, and driven close with a beetle, and 

 thus the sixteen stones, which formed the circle, were 

 set in their places. The slips of Purbec were then 

 driven into their holes, and lastly, the cramps, Fig. 6. 

 which were meanwhile getting hot in melted lead, were 

 put in their places, and the melted lead poured in to fill 

 up the holes. Thus the circle was made both firm 

 and water-tight. 



