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I. A Letter from the Rev . Henry Miles 
D. D. & F, R . S. to Martin Folkes Efq; 
\ c Fr. R. S. concerning Thermometers, and 
fome Obfervations of the Weather. 
^ ^ ' j 1 lu'.> 
Read Jan. Candor with which you receive 
1748 JL whatever is prefented to you, tend- 
ing to advance Natural Knowledge, invites me to 
offer this Paper to your Hands, on the Subject of 
the Thermometer. . . 
It has been often complained of, that the /Theo- 
ries we have of the Air and Weather, are fo im- 
perfect, and that an unfinifhed one, of the honoura- 
ble Mr. Boyle, publilhed fince his Death, Ihould be 
the beft we yet have > perhaps there is equal Reafon 
for Complaint, that the Thermometer firft intro- 
duced into Ufe in England by the fame excellent 
Philofopher, fhould be fo little improved for more 
than half a Century of Years, and be made to ferve 
a not much better Purpofe than that of Amufe- 
ment. .7 ,rn ’-.orr; x . 
For fome Years pall, fcveral eminent Philofophers 
at home and abroad have applied tjhemfelves to bring 
this Inftrumcnt to greater Perfection, and to render 
it more ufefulj and .among them the great Sir- 
Ifaac Newtofi did not think it -unworthy, his At- 
tention. . , 
It feems now to be pretty generally agreed, that 
Thermometers made with Quickfilver are preferable 
A to 
