The sun., 1891-07-05
Winds and Currents OF the Atlantic.

some very Interesting 10cts appear upon
the chart Just issued by the photographic
Bureau to exhibit tho drift OF bottles thrown
into the North Atlantic Ocean at different
points for the purpose OF determining tho
direction and velocity Of the surface cur
rents OF the sea. The average distance trav-
ellcd by 1l3 bottles, In mean period OF $50
days, was 500 miles. and the average rate Of
drift was 6S miles day. Since many OF the
bottles were found on sea beaches, and as
the length OF their stay upon the beach be-
fore they were discovered Is unknown, al
though necessarily counted In the total
time elapsed since they were thrown
overheard. 1t Ia evident that the
average velocity OF drift mentioned is con-
siderably under the truth. The greatest
velocity shown Ia 1877 miles a day, and the
least 0.8 OF mile day. 1t should he said
however. that the smallest velocities in the
tables accompanying the chart are exhibited
by bottles that had been adrift for COM
paratvely short times. and had not, there
fore, been exposed to the effects Of long
continued or successive gales. In some
cases. however, velocities above the average
are shown by bottles that had foated only
o short time.
The first general fact that strikes the eye
In viewing the chart is that the bottles fol-
lowed the known tracks OF storms, and the
direction Of ocean currents whose existence
has been ascertained In other ways. Those
thrown over near the coast OF the United
States travelled along the path Of the Gulf
Stream as far as 1t is clearly traceable and
then continued on In the general course
pursued by cyclones. which cross the North
Atlantic and reach the British Isles. Those
thrown over 10 mid-ocean half way between
Newfoundland and the coast Of Europe, gen.
south as the latitude Of the Cape Verde ISL
ands, and then, turning westward with the
trade winds, ended their adventures among
the West India Islands. Bottles started be-
tween the projecting shoulders OF Africa
and South America also dritted In north
westerly direction until they reached the
Windward Islands.
There is striking appearance OF great
whirl in the ocean, two or three thousand
miles in diameter. and centred In the middle
OF the Atlantic, as indicated by the paths of
the bottles drawn on the chart. The I'M
agination is impressed with the suggestion
OF individuality and Of life and motion that
these great current lines give to the sea.
One interesting characteristic OF the drift
OF the tell-tale bottles Is that In almost every
case where bottle was thrown overheard
within a few hundred miles OF land, 1t drlfted
straight ashore as II impelled by some at
traction. In many cases an island was the
nearest land, and the bottles foated direct
to the island as though 1t were the fabled
mountain Of adamant In the Arabian Nights,
that had the power OF drawing ships from
afar into Its deadly embrace. Two bottles
dropped into tho sea some 500 miles from the
coast OF Africa, and about 200 miles apart, In
~ or % Of north latitude, were found to have
met at point on tho African shore nearly
four months alter their voyage began.
Other equally curious Indications OF tho
play Of winds and currents over the never
resting Atlantic can be seen In this interest
ing little chart; and their study may event.
ualIy lend to important advances In mans
knowledge and mastery OF the seq.