34 z -D**, blagden on tty Heat of 
tucket fhoals, a diftance of more than 1000 miles from the 
gulf of Florida! According to the calculation I have be- 
fore adopted of a lofs of two degrees of heat for every f of 
latitude, the temperature of the Gulf-ttream here would be 
nearly 73 0 ; the difference of which from 59 0 , the heat that I 
obferved in the fea- water both before and after the gale, might 
eafily be perceived by the matter of the veliel. This was in 
the winter feafon, at the end of December. 
An opinion prevails among teamen, that there is fomething 
peculiar in the weather about the Gulf-ttream, As far as I 
could judge, the heat of the air was confiderably increafed by 
it, as might be expected ; but whether to a degree or extent 
fufficient for producing any material changes in the atmofphere 
mutt be determined by future obfervations. 
Perhaps other currents may be found which, iffuing from 
places warmer or colder than the furrounding fea, differ from 
it in their temperature fo much as to be difcovered by the ther- 
mometer. Should there be many fuch, this inttrument will 
come to be ranked among the mott valuable at fea ; as the diffi- 
culty pf afcertaining currents is well known to be one of the 
greateft defeats in the prefent art of navigation. 
In the mean time, I hope the obfervations which have been 
here related are fufficient to prove, that in eroding the Gulf- 
ttream very effential advantages may be derived from the uff 
of the thermometer : for if the matter of a ffiip, bound to any 
of the fouthern provinces of North America, will be careful 
to try the heat of the fea frequently, he mutt difeover very 
accurately his entrance into the Gulf-ttream, by the fudden in- 
creafe of the heat ; and a continuance of the fame experiments 
will fhew him, with equal exadhiefs, how long he remains in 
it. Hence he will always be able to make a proper allowance 
1 for 
