o 0 8 Dr, Blagden’s Experiments on 
this irregularity in the experiments is in part to be afcribed to 
an impurity in the fait of tartar ; a turbid appearance, and at 
length a depofition, took place in all thefe folutions, but prin- 
cipally in the llronger, occafoned probably by tartar of vitriol, 
with which that fait is fo frequently mixed. 
The mineral alkali I tried, which was the cryftallized foda 
of the fhops, fhewed no increafe of ratio j but the fcale of its 
operation was too fmall for a proper judgement to be formed* 
Mineral Alkali. 
Proportion of 
Freezing 
Freezing 
water to alkali. 
point by 
point by 
experiment. 
calculation. 
io : i 
O 
3°~ 
29V0- 
5 *• i 
2 7 x 
2 7t 
This fait would not remain fufpended in much greater pro- 
portion in the cooled water. I confider the folutions as de- 
creafing in their freezing point by an equal ratio : pofhbly, if 
the fait of tartar had been cryftallized, and perfectly fatu- 
rated with fixed air, it would alfo have a&ed in the manner 
of a neutral fait, and produced no increafe upon the ratio. 
My volatile alkali, being the fal volatilis falis ammoniac!, 
was tried only in two proportions* 
Vola- 
