[ ] 



CHAP. IL 



H E exceflès of heat and cold have, ia 

 fome inftances, near the fame efië6V : fire 

 bliflers the Ikin ; and, in the coldeft feafons at 

 Hudfoii's Bay, and in the northern parts of Eu- 

 rope, the touch of cold iron, &c. is dangerous^ 

 for metals, by their greater gravity, are, in pro* 

 portion, colder than fro2en water ; and, if touch* 

 ed by the hand, will blifter and t:ake off the fkin. 

 A fort of chemiftry m^y be performed by froft 

 as well as by fire. A friend of mine, who refided 

 fome years at pur fettlements at Hudfon's Bay, 

 in North America, told me, that on broaching 

 a barrel of lime-juice, for the ufe of their fadto* 

 ry, they found it to be hard frozen, which obli* 

 ged them to take off the hoops from the barrel, 

 and chop off fome of the ice for their ufe : this, 

 when melted, they found to be almoft as infipid 

 as water j and concluded, that the whole cafk was 

 fpoiled, and of no ufe ; but, on breaking farther 

 into the ice, they found in the centre of it a fmall 



K 2 quantity 



