30 Account of the Erection cf' the Bell Rock Lighthouse. 
these extensive operations, not a single stone was lost, or even so 
damaged as to render it unfit for the building, notwithstanding 
the numerous changes and shiftings from hand to hand, which 
each stone underwent before it was finally laid with mortar. 
In some instances, indeed, blocks of stone were lifted from their 
beds by the run of the sea ; but none were carried entirely 
away. 
The fixtures for the door and window-hinges are of a pe- 
culiar construction,^ and seem to be admirably suited to the si- 
tuation ; their composition, of tin and copper, is the best that 
could be devised. Their form cannot easily be described, but 
will be readily understood by examining Plate XIX. of Mr 
Stevenson’s work. The weight of a set of these hinges, with 
their Lewis-bat tails and boxes, is no less than 2 cwt. They 
are so applied as to be easily withdrawn and replaced, without 
interference with the masonry. 
The trenailino’ and wedmno; with oak timber was continued 
to the height of upwards of forty feet, or throughout the solid 
part of the building. But Mr Stevenson is induced to con- 
clude, that trenailing should be resorted to only under very par-r, 
ticular circumstances, as the boring of the trenail holes is apt to 
disturb the bond or connection of the last laid course. It is on- 
therefore, where the walls are to be exposed to the heavy 
wash of the sea that trenailing should be applied. The stair- 
case was constructed like that of the Edystone. 
When the light-house had attained the height of the stair- 
case, it admitted of full day’s work to the artificers; when ma- 
terials could be landed, they had even, not unfrequently, pay 
for six extra hours per day, and were thus in the receipt of 
about two guineas of wages and premiums per week, while the 
foremen had double allowance. The whole were kept board-free 
at the rock ; and even the postages of their letters were paid. ‘ 
In Plate I. v/e have given an elevation and section of the 
light-house, to which we refer our readers. We have already 
noticed the manner of attaching the lower courses of the stones, 
which was similar to that resorted to at the Edystone, and we shall 
now advert to the plan followed for the upper or habitable part. 
At the stone stair-case, leading from the door to the first floor, 
the walls are of the medium thickness of about seven feet ; this 
