WATER AND THE OCEAN. 



91 



would have obtained a hard ice as well as Mr. Nairne, which, by a 

 more perfed congelation, would have excluded the briny particles 

 intercepted between the 11)1/2 lamince, adhering to each other weakly ; 

 and would have connected the laminae, by others formed by frefh 

 water. The Dr. found afterwards, it is true, thicker and fomewhat 

 more folid ice, in the velTel B : but the fea- water had already been 

 fo much concentrated by repeated congelations, that it is no won- 

 der the ice formed in it, became at laft brackiih : it fhould feem then, 

 that no conclufive arguments can be drawn from thefe experi- 



ments. 



There are two other objedlions againfl the formation of the ice in 

 the great ocean; thejir/i is taken from the immenfe bulk and fize of 

 the ice maifes formed in the ocean, which is the dcepejl mafs of water 

 we know of^. But the reader is referred to the table communicated 

 above, where it appears, that in the midil of fummer, in the lati- 

 tudes of ^z^\ 550 26', and 64° South, at 100 fathoms depth, the ther- 

 mometer was at 34°, 34^° and 32°; and that in all inflances, the dif- 

 ference between the temperature at top and at 100 fathoms depth, 

 never exceeded 4 degrees, of Fahrenheit's thermometer, or that the 

 temperature of the air did not differ five degrees from that of the 

 ocean at 100 fathom deep. If we now add to this, that beyond 



ICE, 



\ 



N .2 



the 



* Dr. Higgins's experiirsents, in the fecond fupplementto tlie Probability, 5cc. p. 141. 



X 



