of a SM fs AjjprQOch to Land. 
the dark olive-green tintj denoting soundings, when it immedi- 
ately fell to 66°, though then no bottom could be found with 
110 fathoms of line. And when abreast of Cape St Vincent, 
at about four miles distance from the pitch of the Cape, it on- 
ly stood at 61° ; but ascending, as we left the Portuguese coast, 
steering for the entrance of the Gut of Gibraltar, it again 
reached 69°. ( Vide Table under date of October 17.) 
In working through the Strait of Gibraltar, the mercury in 
the tube ranged from 60^ to 66°, falling as we approached either 
the Spanish or -the Barbary shores; but lowest on the latter, for 
which it is easy to account, as we stood much nearer it, the 
shoals and rocks to the westward of Tariffa Island rendering it 
imprudent to approach the Spanish coast too • near ; while the 
dangers in Tangier Bay, and off Cape Malabat, lie no great 
distance out from land : this induced me to prefer keeping 
clearest to the African coast. 
On the coast of the. United States of America, no vessel 
need run ashore without a previous warning of the proximity 
to land, if there is only a thermometer on board, and it is regu- 
larly attended to. However inaccurate the reckonings of the 
navigators on board may be, let iis hope that, upon due exa- 
mination, 'it will be found this instrument is not only invaluable 
on that side the Atlantic, but that it will be a faithful monitor 
of the approach to land or shoals throughout the ocean, or 
at any rate to the northward of the Tropic of Cancer, and pro- 
bably to the southward of that of Capricorn. 
Thermometrical Table extracted from a Journal Icept on Board ‘ 
the Ship Asia, from New Orleans to Gibraltar, 1818. 
Month. 
Lat. N. 
Long, W. 
• 
< 
Time of 
Observ. 
Remarks, &c. 
Aug. 2T. 


90° 
88° 
Noon. 
f At anchor at Balize, river 
1 Missisippi. 
28. 
89 
88 
Ditto. 
Ditto.. ditto. ditto. 
29. 
88 
88 
Ditto. 
Ditto. ditto. ditto. 
— 
89| 
88 
7 A. M. 
j Outside the Bar of the 
^ Missisippi. 
< Greatest heat of water. Bar 
30. 
881 
90 
1 P. M. 
bore N. 62° W. distance 
I 28 miles. 
28® 36' 
88® 27' 
87 
87 
8 A. M. 
j The days arc reckoned ac- 
1 cording to sea account. 
* T. A. temperature of the air, T, W. temperature of the water. 
