C 6i 3 ] 
IX. A Letter from the Reverend Henry Miles 
D. D. to Mr. Henry Baker F. R . S. con- 
cerning the Difference of the Degrees of 
Cold marked by a Thermometer kept within 
Door$y or without in the open Air . 
Dear Sir, 
Read Dec. ip. 1 T SEND you herewith an Extrad from 
my Regifter of the W eather, fhewing 
the State of my Barometer and Thermometers, for 
fome Days of laft Week : in which you will obferve 
a fudden Change of the Temperature of the Air, 
particularly on Thurfday Morning the 3d Inflant, 
and, by the fame, you may fee the little Ufe a 
Thermometer is of, when kept within-doors, to 
determine the State of the Air abroad, $$ to He;at 
or Cold. 
I have two Thermometers filled with Mercury, and 
of the fame Conftrudion, made by the late Mr. Sif~ 
fon, in the Strand- The one is placed without my 
Chamber -Window, in a North-eaft Situation, under' 
Covert, contriv'd to admit a free Paflage of the Ait*, 
but to keep off Sim and Rain; the other hangs; 
within the Window, about three Feet from the 
former, where the Sun never fall? ; on -it-: Thd 
Room is conftantly -Ojceupiedj as a B;fd -Chamber, 
but has had no Fire in Jt this Seafon, — ; 
It appears byfthe adjoining. Table, that onTuefday 
the ill inftant, at 8 in the Morning, ^he. ThernjOb 
meter without flood at 17 Degrees above o- rot 
freezing Point ; that within at 14. At 9 at Night, 
that without was at 6- and that within at i-a above 
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