of the common Air at Sea. 367 
as I have attempted to prove in my book upon Vegeta- 
bles, p.107: in the prefent cafe, however, I rather incline 
to thinks that the reafon why the air, gathered in rainy 
and windy weather on the fea, was found of an inferior 
quality, is to be afcribed chiefly to the land air being 
driven by the wind upon the fea, and thus to the mix- 
ture of both airs. 
November the 6th, about nine o’clock in the morn- 
ing, the weather being cold, windy, and cloudy, I again 
put the common air of Oftend, which I gathered in my 
inn, to the tell, and found it of near as good a quality as 
that in the mouth of the Thames ; for one meafure of it 
with one of nitrous air occupied 094^ in three repeated 
trials. 
The fame morning, about eleven o’clock, the wind 
blowing very hard from the fea, I went to the fhore on 
purpofe to gather fome air juft as it came from the fea. 
I found its quality inferior to that which I had examined 
two hours before, though ftill fuperior to any air I have 
yet found in England; for one meafure of it with one of 
nitrous air occupied 097. The common air, as I found 
it in my lodging, was at 098. The wind had not fhifted 
much, though I cannot afcertain the exadfc point from 
which it then blew. It feems probable from the fore- 
going experiments, that though in general the fea air 
2 furpafles; 
