it& cure. 



10 CURE OF THE DRV ROT. 



Fafts and obfer- What particularly attra6led my obfervation to the circurn- 

 ing °he dry m"" ^^"^^^ ^^^ ^'^'^' ^''^^ ^^^^'^ Oak. and fir pofts were brought 

 in timber, a.id into this premature llate of decay, from their having been pain- 

 ted prior to the due evaporation of their moiflure; and then 

 extending the obfervation, and tracing the hifiory of other 

 wood at!e£ted in a fimilar manner, I am convinced that the evil 

 frequently thus originates, and its prevention would be in ufing 

 timber, previoufly well dried and feafoned. 



RICHARD RAMSDEN BRAMLEY. 



SIR, " 



A conliderable time has elapfed iince I furniflied you with 

 fome obfervations relative to the dry rot in timber, and having 

 been fince engaged buiily in draining from 4 to 5000 acres of 

 ground, further ideas on the fubjedt of the dry rot have in the 

 interim recurred to me from the work I have been engaged in, 

 which, if the refpe€lable Society to which you are Secretary think 

 worthy attention, they may add to, or connect with my former 

 ideas, as may be deemed moft ufeful. Where houfes are 

 troubled with damp walls, near to the earth's furface, it is 

 generally, if not univerfally, occafioned by the percolation 

 of water from the higher adjoining ground, which, thus in- 

 tercepted in its current, attempts to follow the general hydrof- 

 tatic law, of elevating itfelf, by the fyphon line, to a height 

 equal to that from whence it has its origin. Thus, in houfes 

 differently fituated, we fee the damp arifing, to varying de- 

 grees of height, on the walls ; and thofe are probably all cor- 

 refponding to the height at which the moifture circulates in the 

 adjoining ground. At its firft entrance to the building, and 

 whilft the moiflure is in fmall quantity, the excavated part 

 of the foundation wall may abforb, and gradually quit fuch 

 proportion; but the excefs, as is generally the cafe in moifl 

 weather, exceeding that power, the foundation (tones are then 

 faturated in a more rapid proportion than the adjoining rarified 

 internal atmofphere can evaporate: the watery particles then 

 creep up, in degrees proportionate to the afcent from which 

 they originally defcended, excepting when prevented, or 

 driven off by the fuperior heat of the adjoining rooms, when, 

 in addition to the difagreeable damp they caufe, they fre- 

 quently occafion confiderable damage to pictures, furniture, 

 &c. Drains laid out athwart the afcending ground, with a 



very 



