the Point of Mercurial Congelation , *365 
Experiment VIII. made December 21, 1781. 
Time per 
watch. 
Mercurial 
thermom. 
Appara- 
tus. 
Spirit 
thermom. 
Remarks and Occurrences. 
> , „ 
10 58 30 
10 59 0 
i° 59 30 
11 00 
II O 50 
II I O 
i 1 1 3 ° 
11 20 
11 2 30 
1130 
-ii 3 30 
11 40 
11 4 30 
89 
85 
82 
78 
75 
70 
66 
64 
60 
55 
5 1 
45 
44 
381 
38 
38 
38 
38 
38 
38 
38 
38 
38 
37 ! 
37 ? 
37 
27 ! 
271 
2 7 § 
2 7 i 
2 7 i 
271 
271 
2 7 l 
271 
2 7 f 
27 
27 
2 7 
Stirred the mixture. 
Stirred the mixture. 
— 
This eighth experiment was made with a view to try, whe- 
ther quickfilver would freeze whilft in contact with the freezing- 
mixture. For this purpofe I did not ufe the apparatus em- 
ployed in the other examples, but fubftituted another, by 
taking a gallipot made of flint ft one (as being thinner than 
the common fort) of about an ounce meafure, and filled it 
halt full of quickfilver, into which I inferted the mercurial 
thermometer (B) and employed the other mercurial thermome- 
ter (A) as an index, as before. I hoped by this means to deter- 
mine exa&ly when the quickfilver was congealed, as I had free 
accels to it at all times, which was not the cafe when inclofed 
in the cylindrical glafs, the worfted wound round the tube of 
the ivory thermometer to exclude the air, equally excluding any 
inftrument from being introduced to touch the quickfilver. I 
made a kind of fkewer, with a flat blunt point, of dried cedar 
wood 
