high Winds or Calms ? whether in wet weather or dry ? whe- 
ther moft when a North, or when a South , when an Eaft or a 
Weft wind blows ? and whether it keeps the fame feafons of 
Changes? and whether the feafons and changes of the Air 
and Weather can be thereby difcovcr’d , and the now hidden 
caufes of many other Phenomena detedfed ? 
■ The faid Doctor is fo much pleafed with the difcovery alrea- 
dy made by the help of this Inftruinent,thathe thinks it to be 
one of the moft wonderful that ever was in the World , if we 
fpeakofftrangenefs,and juft wondered ofPhilofophical im- 
portance, feparate from the intereft of lucre. For ( faith he, in 
one of his Letters ) who could ever expe<ft, that we men fhould 
find an Art, to weigh all the Air that hangs over our heads, in 
all the changes of it, and, as it were, to weigh, and to diftinguifh 
by weight, the Winds and the Clouds ? Or, who did beiiev^ 
that by palpable evidence we ihould be able to prove, the fere- 
nefl Air to be moft heavy, and the thiekefl. Air, and when darkeft 
Clouds hang neereft to us, ready to diifolve, or dropping, then 
to be lighteft. And though ( fo be goes on') we cannot yet reach 
to all the fifes and Applications of it $ yet we fliould be en* 
terrain d for a while , by the truly Honourable Mr. Boyle , as 
the leading perfon herein, upon the delight and wonder. 1 he 
Maynet was known many hundreds of years before it was ap 1 
plied to find out New Worlds. To me ( faith he) tis a wonder- 
ful delight, that 1 have alwaies in my Study before my eye fuch 
Having thus in SV^Wexpreffed his thoughts about this In- 
vention, and the Angular pleafurc, he takes in the Obferva- 
tions made therewith, he defcends to particulars, and in feve- 
ral Letters communicates them to his Correfpondenr, as fol- 
lows : 
s. My Wheel-barometer I could never All fo exatftly with 
Mercury, as to exclude all Airs and therefore I truft more 
Y ' to 
