434 Capt. Sabine on the Velocity and Temperature, §c. 
The observations in the passage from Trinidad to Jamaica, 
indicate a general set of the surface-water across the Caribbean 
sea towards the Gulf of Mexico, averaging about sixteen miles 
in each twenty-four hours. The northerly inflexion, on ap- 
proaching Jamaica, was occasioned by the indraft between 
Cape Tiburon and Point Morant. 
From Jamaica to the Havannah the Pheasant was engaged 
in conducting a convoy, which obliged a suspension of the 
observations. 
In crossing the Caribbean sea from Trinidad to Jamaica, be- 
tween the 9th and 17th of October, the temperature of the sur- 
face-water, observed always at 8 A. M., and occasionally at other 
hours, was never less than 82°°8, nor more than 83°; between 
Jamaica and Grand Cayman, on the 10th and 11th of No- 
vember, the minimum was 83°, and the maximum at 3 P.M., 
83°°8; from the Cayman Islands to the entrance into the Gulf 
of Mexico, between Yucatan and Cuba, and in the open part 
of the Gulf itself, the surface varied from 82° to 82°°5*; but 
on 
of the atmosphere was the subject of very frequent and careful observation 
on each day; "@o effect of the river, however, on the state of the aqueous 
vapour was perceptible; the point of deposition varied only between 72°°5 
and 74°, and the air between 79° and 82°, the higher temperatures of 
both taking place when we had arrived abreast of Surinam, and the sur- 
face water had increased to 83°. In the Gulf of Paria, where the general 
temperature of the surface is raised to 84°-5, by the admixture of the heated 
water from the smaller branches of the Orinoco, the air was further aug- 
mented to 84°, and the point of deposition to 75°°5 Between Point Ga- 
leotta and Port Spain, we crossed the stream of one of the branches of 
the Orinoco, the temperature of which was 85°°5, and the specific gravity 
not more than 1:0064; the general surface of the Gulf being 1:0204. 
* The particular observations were as fcllows, and are accompanied by 
the temperatures of the air, and of the point of deposition, observed at the 
same hours. 
Between : Between 
Trinidad and Jamaica. Port Royal, Jamaica. Jamaica and Havannah. 
Point of 
Depos. 
Water. 
Point of 
10 A.M. 
noon 
7 AM. 
2 P.M. 
noon “ 
ot A.M. 
noon 
19 A.M. 
10 
1D WI, 
dle of the harbour 81°°5, at 
sunrise ; 83°5, at 2 P.M. 
In the offing 83°; in the mid- 
