Natural History of the Ocean^ ^c.- 129 



daqce of red fish. Near Sumatra and on the coast of Chili, 

 fhe water seems red from a minute vegetable substance 

 that floats in it. 



Temperature. — At the Equator, the surface water is 80°; 

 Farenh. ; at 28 N. Lat. it is 68^ ; at 47 N. Lat. it is 58°; 

 in the arctic regions it is about 30^ ; diminishing as the 

 latitude increases. 



The temperature, at a considerable depth, is higher on 

 approaching a coast ; but at a distance from land it dimin- 



Wl 



1 



and the surface water 10° ; it will be perhaps on!} 25° at 

 the depth of 50 fathoms. The reverse of tfiis was supposed 

 to be true in lakes, but llie late experiments of M. de la 

 Beche, prove the Swiss Lakes to agree in this particular 

 with the variations of ocean temperature. 

 ♦ The dimimition oi^ temperature on the banks of New- 

 foundland is so great, that the thermometer may justly be 

 considered as an indicator of the approach to land on the 

 east coast of the U. States. 



The Gulf Stream is about 15^ warmer than the surround- 

 ing bed of the ocean. Summary — 



1. The temperature of the ocean diminishes from the 

 Equator to the Polar regions. 



2. It decreases near Islands and Continetifs. 



3. It diminishes in w^ide seasj according to the depth 

 from which it is drawn : except in the polar seas, where 

 the reverse obtains. 



4. It is less on sand banks. 



Remarks. — It is owing to the extreme mildness and equa- 

 bility of temperature enjoyed by the ocean and superna- 

 tant atmosphere, that the good eflTects are derived from sea 

 air in pulmonary complaints: and not from the saline hu- 

 midity of the air, as has been asserted. This circumstance 

 has not been sufficiently insisted upon by medical men. 

 We may learn from it the utility of sending patients on a 

 voyage into the wide ocean, where the air is not aifected 

 by the various changes on land; we may also see the inu- 

 tility of coasting voyages for consumptive persons. 



Specific Gravity. — The experiments of the celebrated 

 Capt. Scoresby, Dr. Marcet, and Dr. Traill sanction the 

 following: inferences. 



^ 1. The sp. gr. of the waters of the Atlantic decreases 

 from the Equator to the poles: being at the Equator 1.0295 ; 



Vol. v.— Xo. 1. 17 



