72 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



carefully corrected for the influence of the pressure of the 

 water. Lenz deduced the important conclusion that there 

 is at and under the equator a belt of water cooler than 

 the water to the north and south of it, the existence of 

 which is explained on the principle that there must be a 

 flow of warm surface water from the equatorial regions to- 

 ward either pole, and which must be accompanied by a cor- 

 responding flow toward the equator in the lower regions of 

 the ocean, so that at the equator itself, where the two deep- 

 sea currents meet, cool water rises to the surface. This prin- 

 ciple has been independently propounded by Dr. Carpenter 

 to explain the cold band between the Gulf Stream and the 

 United States coast, and justifies him in the statement that 

 his own researches during the past ten years have but afford- 

 ed a confirmation and elaboration of Lenz's doctrine of oceanic 

 circulation. 12 A, X., 170. 



NEW GENERALIZATION IN OCEAN PHYSICS. 



A new generalization of much importance in reference to 

 ocean physics has lately been derived from the observations 

 of the Challenger in the Malay Archipelago during her re- 

 cent passage from Cape York to Hong-Kong. The seas vis- 

 ited, we are told, consist of a series of sunken lakes or basins, 

 each surrounded and cut off from the neighboring seas by a 

 shallower rim or border. There is a general oceanic circula- 

 tion down to a depth equal to that of the border, and the 

 temperature gradually decreases from the surface to this 

 level. The entire mass below, however, having no communi- 

 cation with the outer water, and consequently no circulation, 

 remains at nearly the same temperature as that flowing over 

 the floor of the rim ; or, in other words, the water coming 

 along the floor of the ocean from the antarctic seas, which is 

 found in all the deep open channels, can not obtain admission 

 through or over the rim. 



On this account the bottom temperature depends entirely 

 upon the altitude of the encircling rim. Thus, in Torres 

 Strait, with a depth of 2450 fathoms, and a rim reaching 

 within 1300 fathoms of the surface, the body of water be- 

 low that depth lias a steady temperature of 35! The Sulu 

 Sea, which is 2550 fathoms deep, with a rim reaching within 

 400 fathoms of the surface, has a temperature to its bottom 



