37 6 The Conclufeon* 
bably alfo be of good fervice to purify 
gradually the thick rancid fumes which arife 
from the dung of hot beds, and are often 
very deftrudive of the tender plants : This is 
to imitate Nature, which while fhc provides 
for the defence of living creatures againft 
the cold, by a good covering of Hair, Wool, 
or Feathers, at the fame time fhe takes care 
that the air may have admittance through 
innumerable narrow meanders in fuch quan- 
tities as may be fufficient to carry off the 
perfpiring matter. 
I have here, and as occafion offered under 
feveral of the foregoing Experiments, only 
touched upon a few of the mod obvious 
inftances, wherein thefe kind of refearchcs 
may poffibly be of fervice in giving us ufe- 
ful hints in the culture of plants: Tho' I 
am very fenfible, that it is from long ex- 
perience chiefly that wc are to exped the 
moll certain rules of pradice \ yet it is with- 
al to be remembred, that the likelieft method 
to enable us to make the mo ft judicious 
obfervations, and to put us upon the moft 
probable means of improving any art, is to 
get the beft infight we can into the nature 
and properties of thofe things which we are 
defirous to cultivate and improve, 
