1858.] The Temperature of Hie Surface of the Ocean. 171 



made double observations, i. e. I registered the air and sea from 

 both Thermometers alternately. The result was the same. 



3. On the 29th at 3 p. m. the air and sea were 86°. At 6 p. M. 

 a squall came on with heavy rain, which lasted, tiie rain, for 6 hours. 

 This cooled the air from 86° to 82° but the temperature of the Sea 

 fell 2° only in the same time. 



4. On the 3rd at 3 p. m. the air was 85° the sea 86°. "We 

 had a squall and a shower of a rain at 8 p. m. ; on the 4th at 9.30 a. m. 

 the air had fallen to 83° the sea to 84° only. 



5. Since we approached the equator i. e. since we passed 5° 

 North, I have observed that the mercury does not fall more than 

 2 degrees from the evaporation of the moisture on the instrument. 

 North of 12° it used to fall 6 degrees. 



6. For the first 7 days the observations were taken ou the main 

 deck at the Poop-ladder in the shade, since then they have been 

 taken in a starboard Poop Cabin aft the Cuddy with open port 

 and jilmills ; and I think that the situation is preferable from 

 equability of shade to the deck, or any other part of the ship for 

 registering the temperature of the air. 



7. In the Indian ocean we found the South East trade blowing 

 in the 8th degree of S. Latitude, and we left it in 27° . 



8. To the West of the Cape we found the South East trade in 

 31° and left it in 1° South. 



9. Pound the North East trade in 6° North and carried it to 

 25°. Pound the sea weed in Latitude 19°, Longitude 39° West 

 and lost it in Latitude 31°. 



10. On the 21st of March Latitude 24° 38' Longitude 5i°-l2> 

 the morning was calm, Thermometer in air at 9^ a. m. 80° sea 

 79°. At 2 P. M. we had a squall from the South West which 

 reduced the temperature of the air to 76° at 3 p. h., but the tem- 

 perature of the sea was 80° . It had risen 1 degree before the 

 squall, I presume, and had not diminished by 3 p. M. 



11. On the 25th March in Latitude 29° 51' Longitude 40° 17' 

 we had the wind from the North, a land wind from the Island of 

 Madagascar. The Thermometer in air at 9£ a. m. stood at 79° ; the 

 temperature of the sea was 75J. At 3 p. M. the temperature of 

 the air was 82° (sea 80°) or 7° higher than on the preceding day 

 when the temperature of the air at the same hour with the wind 

 from the South East was 75° only. Ou the 26th the wind was again 

 from the South, the air fell to 77°, but the sea had not cooled with 

 equal rapidity, and stood at 79°. A. Campjjell. 



