EXPLORATIONS, WESTERN ATLANTIC, STEAMER BACHE, 1914. 11 



Between 200 and 800 meters, and again below 1,200 meters, the 

 greatest difference is only 0.6°, hardly more than the probable error 

 of the curves from which the table is constructed. Above 200 meters 

 the CJiallenger series is decidedly the warmer; but this difference is 

 probably due to the geographic location of the stations, the tempera- 

 ture of 1914 (fig. 1) suggesting that in that year also the surface 

 reading would have been above 21° at the locahty of the Challenger 

 station. Between the 800 and the 1,200 meter levels the tempera- 

 tures were from 0.6° to 1.5° lower in 1873 than in 1914; but here again 



Temperature, Centigrade 



„ 3 4 B** 6 7 8 9 10° 11 12 13 14 15M6 17 18 19 20^21 22 

 Meter 



100 



200 



300 



400 



500 



600 



"700 



800 



900 

 1000 

 1100 

 1200 

 1300 

 1400 

 1500 

 1600, 

 1700. 

 1800 



Fig. 5.— Temperature sections between Bermuda and the Bahama bank; stations 10185, 10187, 10191. 



it may be the difference in geographic location which is responsible, 

 the lower temperature of the Challenger station at this depth being an 

 indication of the general and well-known upwelling of abyssal water 

 toward the Equator. Indirect evidence to this effect is afforded by 

 the fact that these Challenger temperatures agree ahnost exactly, 

 below 800 meters, with Bache station 10212 on nearly the same 

 latitude north of the Bahama Bank, and they do not differ from the 

 latter by more than 1.4° at any depth, as illustrated in the preceding 

 table (p. 10). 



