[ r- 3 
X. Account of an Improved Thermometer. By Mr. James Six ; 
comunicated by the Rev. Mr. Wolladon, F. R. S. 
Read February 28, 1782. 
A TTEMPTING fome time ago to afcertain the greated 
degree of heat and cold that happened in the atmo- 
fphere each day and night, or during the courfe ot twenty-four 
hours, I experienced the inconvenience which attends thermo- 
meters commonly made ufe of for that purpofe ; the necedity 
I mean of the obferyer’s eye being on the indrument the very 
indant the mercury dands at the highed or lowed degree : for, 
fince the time when that may happen is utterly uncertain, if it 
be not immediately noticed, it can never after be known. The 
fultry heat of the fu miner’s days, and freezing cold of the 
winter’s nights, which is commonly mod fevere at a late un- 
feafonable hour, render it very unpleafant to be abroad in the 
open air, although it is abfolutely necedary for the thermome- 
ter to be placed in fuch a fituation. Ingenious men of our 
own country, as well as foreigners, have, it feems, long ago 
endeavoured to remedy this inconvenience ; and feveral ther- 
mometers of different condru&ions have been invented for 
that purpofe. van swinden defcribes one which he lays was 
the fird of the kind, made on a plan communicated by Mr. 
Bernoulli to Mr. leibnitz. Mr. kraft, he alfo tells us, 
mad& one nearly like it *. A defcription of thole by Lord 
* Difl". fur la Comparaifon du Therm, par van swinden, p. 253 — 255. 
CHARLES 
