118

THE PRINCIPLES OF BRIDGES.

TRACT 2.

crosslaid; oi' timber: what wood are they made of, and whatare their dimensions or scantlings?”

“ Answer. In general I find nothing between the. stonesand piles, but sometimes pieces of plank, mostly of oak, anda little of elm, some of which is 6 inches and 4 inc. in thick-ness ; which I apprehend were not originally placed there,but only when reparations have been made, on which accountthey were fixed, in order to wedge up tight to the stone-work ; it being impossible to make sound work in that caseby any other method.”

“ Query 5. Are the piles which surrounded the founda-tions of the piers, before the sterlings were added, square orround, rough or hewn, driven as close as possible, or at adistance? If they touch one another, are they fastened to-gether with a dovetail, or by an}' other contrivance of thesame nature; and if they do not touch, at what distance arethey at a mean?”

“ Answer. These piles are round, rough, and unhewn :they are driven close, and touch one another: they do notseem to be fastened together by any contrivance, except thatsome have planks upon them, and some have none. Butthese observations I have made where breaches have hap-pened, so that one might get 1, 2, or 3 feet within the sur-face of the piers: but how they are in the middle of the piers,is impossible to determine.”

“ Query 6. Are the heads of those surrounding piles fas-tened together by any kirb or capcile ? If there be any, letit be described, and its dimensions, by a figured sketch.”

“ Answer. They are fastened by no kirb or capcile.—■There are only planks upon some of them, as I mentioned inthe former answer.”

“ Query 7. Are the inside piles, on which the founda-tions of the piers are laid, round or square, hewn or rough,very close, or at what distance at a mean ; of what timber,and size; are they shod or not?”

“ Answer. This query is very difficult to answer. I canonly say, that I have had an opportunity to examine one