328 PHeMOMENA OF THE OCEAH. jJj,> 
with peculiar sagacity, ascertained to arise 
fence of two tides, one from tire South Sea, and y 
the Indian Ocean. Of each of these two tido jcr, 
successively two every day ; two at one 
two at another which are less. The time ^ 
arrival of the two greater was considered o) 
tirlfi! that between the two less, as ebb. ' ^ 
tide ; that between the two less, as ebb. 
these simple facts in his] possession, that 
tician solved every appearance, and so es 
theory as to silence every opposer. a ^ 
Besides tlie common and [periodical 
LOCAL CURRENTS are met with in dift'eren ’ 
fei-eut parts of the ocean, and for the greatei p 0 .i 
considerable distance from land They have £ .) 
ascribed to particular winds i but their ong'O 
trace, as they havebetn occasionally .;(» 
surface of the water, running in a contrary di .y 
stratutri above, and cannot, therefore, have o 
winds or monsoons, d’hese particular ''vrViii*'*? f /ii 
ascribed to lha immcmse masses ot polar ice, tl'*‘',,A 
a greater degitie of cold in the under [)i;d ! , n 
su-atum of waters; and it has been suspected 
an under current of cold water flowing 
the poles towards the equator, even where 
flows towards the poles. The gre.at 'titerio 
rature which is frequently found in deep ‘ ‘ (.oU' 
i lAv 
0* A 
soundings of the same space of water_ is thus 
The most extraordinary current is that j^jC j,' 
Florida, usually called the gulf-stream, 
the coast of North America to the northwau pC ii' 
and flows with an uninterrupted rapidity. ^ 
the Trade winds, which, blowing from the 
into the gPiat Mexican gulf, cause there an , [ii 
^ ^ LIIGIC- 1’^ 
above tht common level ot the sea. Ihe / 
constantly runs out by the channel where i ,vi 
sistance, that is, tlirough the gulf ot Flot' 
■J 
Biiu'*''-'-, .....-.-a-- a ,rV " ‘ 
force as to continue a distinct stream to a ''y 
A proof of its having thus originated is, tn* , . 
*• . y. . 1 1 /* 1 i 1 lA 
tire gulf-stream has been found to have retail 
lion of the heat it had acquired in the toAW * ^ 
A very singular upper current otteii j|tw 
ward of Scilly, and is highly dangeroirs to 
ward ot &ciliy, aim is lugmy uangciou.^ -- j. 
proach the British Channel. Currents ot m 
