514 Mr. cav allo’s Account oj 
thermometer to 102°; the fmoaking nitrous acid raifed it to 
7 2 0 ; and the marine acid raifed it to 66°; the temperature 
of the room, as well as of the acids, being 64% as mentioned 
above. , 
The apparatus which I contrived for the purpofe of ufing 
the lead: poffibie quantity of ether in freezing water, &c. con™ 
fifes in a glafs tube, terminating in a capillary aperture, which 
tube is to be fixed upon the bottle that contains the ether* 
Fig. 1. of the annexed drawing exhibits fueh a tube,, round the 
. -V / lower part of which, viz. at A fome thread is wound, in order 
to let it fit the neck of the bottle. When the experiment is to 
be made, the hopper of the bottle containing the ether is re- 
moved, and the above mentioned tube is fixed upon it. The 
thread round this tube fhould be moiftened a little with water or 
fpittle before it is fixed on the bottle, in order to prevent more 
effectually any efcape of ether between the neck of the bottle 
and the tube. Then holding the bottle by its bottom FG (fig. 
2,) and keeping it inclined as is fhewn in the figure, the final 
{bream of ether iffuing out of the aperture D of the tube DE, 
is directed upon the ball of the thermometer, or upon a tube 
containing water or other liquor that is required to be congealed. 
Ether being very volatile, and having the remarkable pro- 
perty of increafing the bulk of air, does not require any aper- 
ture, through which the air might enter the bottle, in propor- 
tion as the ether sues out : the heat of the hand is more than 
O 
fufficient to force the ether in a ffream from the aperture D. 
After this manner, throwing the ffream of ether upon the 
ball of a thermometer in fuch quantity as that a drop of ether 
might now and then, for inftance every 10 feconds, fall from 
the under part of the thermometer, I have brought the mer- 
cury, down to 3% viz, 29 0 below the freezing point, when the 
atmofphere 
