128 
Mr. Walker’s Experiments on 
Series II. 
1st. Muriate 
of lime 5, 
Ice-powder 4, at -f 32 0 , 
gave — 41 0 * 
2d. 
— 4 > 
“ 3 > r 20°, 
0 
00 
Th 
1 
1 
3 d - 
4> 
~ 3> - - + 10°, 
- - -54° 
4th. — 
3, 
2, -I 5 °, 
- - — 68° 
In the first experiment, the materials were mixed at the 
temperature of the air. 
In the second, they were previously cooled, by a mixture of 
muriate of ammonia, nitrate of potash, and water ; temperature 
of the air 52 0 ; the salts which formed the preparatory mixture 
being recovered for use again, by evaporation. 
In the third, they were cooled previously, by a mixture of 
muriate of ammonia, nitrate of potash, sulphate of soda, and 
water ; temperature of the air 50°. And, 
In the fourth, by a mixture of phosphate of soda, nitrate of 
ammonia, and diluted nitrous acid ; temperature of the air 49°.-f 
Having concluded my experiments with the muriate of lime 
and ice, I proceeded to try the effects of this salt, prepared so 
as to retain its solid state during summer, viz. of the strength 
1,490, by solution in water; and found that a mixture of this 
kind, produced twenty -nine degrees of cold ; for, by adding 5 
parts of the muriate of lime, in fine powder, to 4 parts of 
water, each at the temperature of -f- 50°, I obtained a cold of 
+ 21 0 : this effect was not improved by the addition of other 
salts. 
* The same experiment made at + 32 0 , with snow, (instead of ground ice,) gave 
-40°. 
f The composition and application of these frigorific mixtures are given in Phil. 
Trans, for 1795. 
