392 
Brick-Making, 
ing through a state of acidity to putrefaction, is of itself 
sufficient to engender mould. Sometimes it is very long 
before mould is produced on particular substances, either 
from the absence of the seed, or the substance not being 
well adapted for its vegetation ; while in others, the seed 
has been known to vegetate in three hours. The mould 
from being first white turns yellowish, and at last blackens. 
As it approaches a state of maturity, a kind of black dust 
falls from it, which is the seed of the plantulse ; a quanti- 
ty of this dust constitutes the powder, which blackens 
the hand when touched. As this dust and seed is so line 
and infinite, it spreads with a rapidity equal to the state 
and condition of the substances which may be fit to re» 
ceive it, and hence may attack a whole building, and be- 
come the means of endangering and eventually destroying 
the most superb edifice. 
Another fact will confirm this reasoning. In pulling 
down the most ancient houses not an atom of dry rot has 
been visible, but merely a decay in the timbers occasion- 
ed by age, because the bricks inside and out were alike 
hard and sound : but where modeni ones have been erect- 
ed on the old sites, a very few years have been sufficient 
to prove, that symptoms of dry rot have manifested them- 
selves in the basement, from the great degree of humidi- 
ty which prevails there. 
If such bricks therefore are not timely removed, all the 
art of man cannot prevent the effects of the dry rot : it is 
the same with certain sorts of stone, which are always 
damp, be the weather what it may, and there the dry rot 
makes the greater havock. 
Besides the bricks made at the places before-mentioned^ 
there are some made at Tooting, of common stocks, at 
Mr. Brodie’s ; at Croydon, by Mr, Cooper ; some very 
good white bricks, and geometrical tiles, at Reigate, by 
Mrs. Lucock; at Send Turnpilce, by Mr. Daws; at 
