t H4 3 
larged into almoft the length of the Cane, without that the 
Counter-prelTure from the Liquors will be in the Icalt altered, 
the hight and weight of the Incumbent CyUnders being al- 
ways the fame. 
That httle alteration that may happen by the dilatation 
and contraciion of the Spirit of Wine by iieat an J cold, w*uch 
ought to be accounted for, may be belt difcovered by a Ther- 
mometer hanging by it (containing the fame quantity ot Spi- 
rit of Wine, and whofe Cane is, as near as may be, of ti)c 
fame Diameter with the C ane BC in the Barometer ) whole 
defcent and afeent muft be added and fubftradcd to reduce it 
to a rigorous exadnefs ; but it is ftili worth while to enquire 
if the Mercury it (elf do not fhrink and fwell with coU and 
heat, fb as not to need this correction. 
Thus is a remedy found out for the defects and inconveni- 
cnces of the Barometers hitherto produced, and an Inftrument 
difcovered, which like a new Sence, will moit nicely fhew 
thofe.^aktu'ations in the Air, which without it would by no 
means be perceptible, and of which undoubtedly very great 
ufcs might be made in order towards a perfect Meteorologies 
which, without fbme fuch help as dus,can hardly arrive at 
any great point of certainty. 
But I forbear to fay more about ji,. leaft ( by omiflion of 
fbme material circumftance ) I fhould prejudice the Ingeni- 
ous Author of this difcovery, who has promifed to publilli a 
more particular account thereof; what is here faid being on- 
ly intended to afTert the Right of the firft Invention of this 
Ufefuland Subtile Inftrument to its proper Author, trom the 
pretentions of all others. 
Ac- 
