[ 6 74 ] 
Although in the experiment made by Mr. Lomo- 
■noffow the quickfilver fell to 1260 degrees, this phi- 
lofopher neverthelefs fays, that he could not fufficient- 
ly obferve, in his hurry, whether the ball might not 
have received fome crack, and the quickfilver thereby 
perhaps might have had liberty to fall the lower, 
which otherwife would not have happened $ for the 
fame thing happened to Med. Braun, Zeicher, and 
/Epinus, that the balls of their thermometers were 
cracked and broken. By the experiment of Mr. 
yEpinus, made on the 25th of December, in which 
the quickfilver fell fuddenly in the thermometer, and 
the cylinder of quickfilver of the thicknefs of one s 
finger becoming folid fo quickly, it may be obferved, 
that the degree of cold then produced ought to ex- 
ceed 300 degrees. Neverthelefs, whatever the de- 
gree be, we cannot determine how the common ther- 
mometer ceafes to be of ufe as loon as the mercuiy 
begins to become folid. 
Here follows an account of the manner, in which 
thefe experiments may be made, that other philoio- 
phers may be capable of repeating them. It is 
therefore to be obferved, that it is neceffary to ule 
fuming fpirit of nitre, or of fuch as is evaporated till 
the fumes become red ; for the common aqua fortis, 
which is ufed, had not the defired effed. Mr. JE- 
pinus has found, that this experiment is very eafily 
and fpeedily made in the following manner. Take 
fpirit of nitre, cooled as much as poffible, and with 
it half fill a wine-glafs, throwing -in as much fnow 
at the fame time, and ftirring it till it becomes of the 
confiftence of pap : then you have almofl in an in- 
ftant the neceffary degree for the congelation of the 
quickfilver. 
