26 Chemical and Physical Notes 



Society in May 1894, and consists of the daily record of 

 "observations by the way," such as it is most important that 

 we should have from the Antarctic Land and Ice. The 

 paper is reproduced almost in its entirety, because its 

 principal usefulness consists in small matters and minute 

 details which would be eliminated in condensation. 



Low Oceanic Temperatures: Ice at Sea and on Land, etc} 



One of the striking features of the ocean discovered by 

 the " Challenger " expedition, was the extensive area of very 

 cold water which occupies the bottom of the sea from the 

 east coast of South America to the ridge which runs north 

 and south in the meridian of the island of Ascension. Here 

 the bottom temperature was found to be 32'5 F. The 

 existence of this exceptionally cold bottom water was dis- 

 covered on the outward voyage in soundings near the 

 Brazilian coast, so that the expedition was prepared to take 

 up the study of it on the way home. This was done very 

 thoroughly on a line from the mouth of the river Plate along 

 the parallel of 35 to the meridian of Ascension. The depth 

 of the water varied from 1900 to 2900 fathoms, and the 

 distribution of temperature in the water was, roughly, a warm 

 surface layer of perhaps 100 to 200 fathoms, then a thick 

 layer of water of temperature about 36 F. down to 1600 

 fathoms near the coast, and to 2200 fathoms or thereabouts 

 at sea. Here was a steep temperature-gradient falling away 

 rapidly from 35 to 33 F., and more slowly to 32'5 F. The 

 occurrence of the steep gradient shows a renewal of the water, 

 and therefore a current. The observations of the " Valdivia " 

 show a similar distribution in lat. 60 to 63 S., with this 

 difference that the surface layer is colder than the inter- 

 mediate one, which is itself colder than the former inter- 

 mediate, being about 34 F. The bottom layer has as low 

 a temperature as 3i'5 F. Unfortunately, there are not 

 enough determinations of the temperature of the deeper 



'On the Physical and Chemical Work of an Antarctic Expedition,' by 

 J. Y. Buchanan, F.R.S. Geographical Journal for November 1899. 



