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grometer, to thofe that firft occurred in all measures 
of phyfical caufes ; and I think that as the latter have 
been furmounted, we fhould not defpair of con- 
quering the former. In a word, it is certain that all 
our inventions only approach towards perfection by 
degrees, without ever attaining to it entirely ; and 
for this very reafon, we have a right to expert they 
will always be drawing nearer and nearer towards 
it. 
Upon thefe notions chiefly, I have raifed my 
hopes, either that my hygrometer will in time be- 
come more perfed, or at leaf! that it may excite 
new ideas, which, will at length, though perhaps by 
fome other road, lead us to a true meafure of the 
humor. As the hope of attaining an end, is one 
of the moft powerful afliftants towards really ar- 
riving at it, I flatter myfelf at leaf! that I fhall have 
given birth to a reafonable one upon this fubjeCt. 
Firjl Views to improve the Hygrometer. 
66. The idea I entertain, that it is neceflary a 
number of attentive men fhould concur, to improve 
the human inventions ; has induced me firft to men- 
tion the general reafons I had, for hoping that the 
hygrometer would be perfected. I fhall now pro- 
ceed to give fome particular reafons on which this 
hope is founded, and which are collected from the 
remarks I have already made upon my inftrument, 
during the little time 1 have had to obferve it. 
The firft, and one of the moft important of thefe 
remarks, is, that the ivory pipe belonging to that 
hygrometer which is always the highdt upon its 
fcale, 
