'v>J 
tj 4 Dr. blag den's Hiftory of 
force it up into the tube, and therefore no fucli appearances 
w ere ohferved as in the former cafe. With regard to M. torn- 
sten’s remark, that when the whole mafs of quickfdver re- 
mained in the ball it hill contracted upon the application of 
heat, the fact is lo improbable, and would be perceived with 
f jeh difficulty, that I have no doubt but he was milled by fome 
prepofleffion. In like manner on the ih of January, when 
the thermometer, having been hationary fome hours at - 6 2°, 
funk in the afternoon to — 1 1 6°, it happened uiiqueftionably 
from the melting and fubfiding of a thread of frozen mercury, 
which had adhered in the tube of the inftrument as high as 
the former degree. None of thefe effeCts could be produced 
when the thermometer had rifen to - 3 1 °, becaufe the cold was 
not then fufficient to congeal the quickfdver. In this eafy and 
iimple manner, does our knowledge of the freezing point of 
mercury enable us to account for phenomena, which were 
thought fo anomalous as to elude every kind of explanation. 
Even fo lately as lad year, one of the mod; eminent philofo- 
phers in Europe, Profefior wilcke of Stockholm, made a vain 
attempt to folve the difficulties by a drained application of his 
doClrine relative to the various fpecific quantities of heat in bo- 
dies, and their different attractions -for the matter of heat *. 
It would now be fuperfluous to add, that the real cold at 
Brunflo was by no means what the thermometer deemed to in- 
dicate^ but probably very little exceeded -39 0 , or the degree of 
mercurial congelation, had not M. tornsten’s obfervations 
been lately reprefented, even in this country, as exhibiting an 
indance of cold actually carried to luch a difproportionate and 
enormous excefs. 
* Ibid. 
Thus 
