"It is obfervable, that the fea- water was a degree and a half 

 colder, ever fince the immerfion -of .the ice, than the frefh water, 

 acted on by the like rnafs of ice, and placed in the like circum- 

 ftances ; and nevertheiefs the ice was difiblved much quicker in 

 the colder fea- water. The quicker folution of the ice in fea- 

 water was evidently the caufe of the greater degree of cold pre- 

 ferved in it during four hours ; and it already -appeared, that 

 fait- water is a more powerful folvent of ice than frem water 

 in the like temperature. And, agreeable to Mr. Barrington's 

 fuggeftion, the matter which impedes the congelation of water 

 muft of courfe facilitate the thawing of ice. The nitrous acid 

 furniflies us with another ftriking inftance to this effect j for no 

 cold can be produced to freeze the water in it ; and a red-hot ladle 

 cannot thaw Lee placed in it, ib quickly as ice is thawed by 

 nitrous acid. 



" At ten o'clock, or in eiglit Tiours after the pieces of ice were 

 firfl placed in the Sea and Thames water, the temperature of the 

 fea-water was thirty-nine, that of the Thames water only thirty- 

 eight. At this time, of the ice in fea-water four ounces eight 

 drachms were diffolved.; of the ice in Thames water, four ounces 

 only were dilfolved. The fea-water being at this period war- 

 mer than the Thames water, correfponds with the fmall portion 

 of ice remaining in it, compared with that remaining in the 

 frem water. The temperature of the room in the place where 

 the tumblers flood, being, by reafon of the fire kept conflantly 

 in it, forty-four or forty-five, for the laft fix hours. 



" In twelve hours, jor at two o'clock in the morning, the 

 temperature of the rcom near the veffels of water being nearly 

 -the fame as formerly defcribed, the temperature of the fea- 

 water was forty, the temperature of the frem water was thirty- 

 nine. Four ounces fifteen drachms of the ice in falt-water were 



diffolved, 



