[ 144 ] 
year the beft? But thefe places will 
not be known till fome accurate 
method of examining the goodnefs 
of common air be in general ufe. 
Is it not fomewhat probable, that 
it is unfafe for the health of people 
to fleep in rooms having windows 
towards a fmall open place crouded _ 
with the branches of a Jarge tree, 
fo. hidden from. the influence of the 
fun as to receive but feldom its 
rays? I remember to have heard 
people fay, that it was unwholefome : 
to fit under a wallnut-tree, and that 
they found themfelves affected by 
its fhade. But I looked upon fuch 
popular ¢ or vulgar errors which are 
- propagated from father to fon. I 
fhould now be inclined to think, 
that an apprehenfion of fome mif- 
f . chict might not be entirely ill- 
a. — 
