PHYSICAL anv LLTERARY. 171 
Sucu a means of producing cold, and 
to fo greata degree, has not, fo far asf 
know, been obferved before, and it feems 
to deferve being further examined by ex- 
_ periments. Till that is done, 1 do not 
chufe to give any account of fome other 
remarkable phaenomena that have occurred 
in the above experiments, nor to enter in- 
to the feveral fpeculations that the fubject 
feems to fuggett. 
SINCE writing the above, I have had 
occafion to obferve, that Mr Richman of 
the Academy of Peterfburg has taken no- 
tice of the effect of evaporating fluids in 
_ producing cold; but does not impute it 
‘to the evaporation alone. His 'very exact 
account of the phenomena, and his theory 
with regard to them, may be feen in Nov. 
Comment. Atad. Petiopolitanae ad aun, 1747 
& 1748, page 284. 
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ART. A ahi 
