I 
Experiments on the freezing of Acids. 169 
ilievvn that oil of vitriol has a ftrength of eafieft freezing; 
and that at that point a remarkably flight degree of cold is 
fufficient for its congelation. 
The refult of Mr. M c Nab’s experiments on the nitrous acid 
is given ill the following table. 
N° 
Decanted part. 
Undecanted part. 
Strength 
of the 
whole 
mafs. 
Strength 
before 
fent. 
Freezing 
point by 
firft 
method. 
Freezing 
point by 
fecond 
method. 
Quantity. jStrength. 
Quantity. 
Strength. 
6 
,561 
-41,6 
— — 
7 
1410 
>445 
2137 
>435 
,439 
>437 
+ *J ,7 
- 3 > 8 
8 
1658 
>390 
194O 
,422 
,407 
,408 
- 3>5 
- 4 
9 
1368 
>353 
2438 
» 4 l6 
>393 
> 39 * 
- 4,5 
— 1 1 
10 
2206 
>343 
1920 
>373 
>357 
>357 
-12,5 
-i 3 > 8 
1 1 
3620 
> 3 ro 
602 
> 3 Sl 
,320 
> 3 2 ° 
-22,5 
-23 
12 
2!55 
,276 
1494 
>293 
,283 
,280 
“ 39 >i 
- 4°>3 
*3 
1618 
,241 
1961 
>235 
,238 
>238 
“34 
-32 
The fir ft column contains the numbers by which Mr. 
M c Nab has diftinguifhed the different bottles. The fecond 
and third columns contain the quantity and ftrength of the 
decanted part of the liquor ; and the fourth and fifth fhevv the 
quantity and ftrength of the undecanted part of the liquor. 
The fixth column gives the ftrength of both parts put toge- 
ther, or the ftrength of the whole mafs ; and the feventh is 
the ftrength of the fame acid, as it was determined before it 
was fent to Hudfon’s Bay. The ftrengths of the decanted and 
undecanted parts were found by faturating the liquor returned 
home with marble ; and that of the whole mafs was inferred 
by computation from the quantity and ftrength of the de- 
canted and undecanted parts ; and as the ftrength thus in- 
ferred never differs from that determined before the liquors 
were fent to Hudfon’s Bay by more than T I._ part of the 
Vol. LXXVII 1 . Z whole. 
