CURRENTS OF THE SEA. 
141 
operation would overwhelm navigation and desolate the -sea ; and, 
happily for the human race, the great atmospherical machine 
(§ 90), which actually does perform every day, on the average, all 
this lifting up, transporting, and letting down of water upon the face 
of the grand ocean, does not confine itself to an area of two hund- 
red and fifty-live square miles, but to an area three hundred thou- 
sand times as great ; yet, nevertheless, the same quantity of water 
is kept in motion, and the currents, in the aggregate, transport as 
much water to restore the equilibrium as they would have to do 
were all the disturbance to take place upon our hypothetical area 
of one mile deep over the space of two hundred and fifty -five 
square miles. Now when we come to recollect that evaporation 
is lifting up, that the winds are transporting, and that the clouds 
do let down every day actually such a body of water, but that it 
is done by little and little at a place, and by hair's breadths at a 
time, not by parallelopipedons one mile thick — that the evapora- 
tion is most rapid and the rains most copious, not always at the 
same place, but now here, now there, we shall see actually existing 
in nature a force sufficient to give rise to just such a system of 
currents as that which mariners find in the Pacific — currents which 
appear to rise in mid ocean, run at unequal rates, sometimes east, 
sometimes west, but which always lose themselves where they 
rise, viz., in mid oceam 
- 271. Under Currents. — Lieutenant J. C.Walsh, in the United 
States schooner " Taney," and Lieutenant S. P. Lee, in the United 
States brig " Dolphin," both, while they were carrying on a sys- 
tem of observations in connection with the Wind and Current 
Charts, had their attention directed to the subject of submarine 
currents. 
They made some interesting experiments upon the subject. A 
block of wood was loaded to sinking, and, by means of a fishing- 
line or a bit of twine, let down to the depth of one hundred or five 
hundred fathoms (six hundred or three thousand feet). A small 
float, just sufficient to keep the block from sinking farther, was 
then tied to the line, and the whole let go from the boat. 
To use their own expressions, " It was wonderful, indeed, to 
see this barrega move off, against wind, and sea, and surface cur- 
rent, at the rate of over one knot an hour, as was generally the case, 
and on one occasion as much as 1| knots. The men in the boat 
