Rocky Ford enterprise., 1894-06-07
CURRENTS INTHE LAKES,
A Study That Is BeinE Carried on
by Means of Bottle-PRpers.

A study That Is being Carried on
by Means of Bottle-Papers.
While the United States weather bu-
fenu WIS making wreck chart of the
great lakes in the winter of 1912, it
was ots. rived that wrecks were cluster
cd in certain parts of the lakes This
suggested the idea that unknown cur
n nts might play considerable part
in wreckngc. The subject had been
very little studied. 1t was decided to
take steps to get some idea what these
currents are. A large number of bot
ties were specially made with the name
of the bureau blown in the glass. Lake
captains received supplies Of bottles
and also printed blanks on which to
write ihe time and place of throwing
the bottles overheard. There were also
printed directions for the finders and
flanked envelopes in which to forward
to Washington the time and place Of
picking up the bottles.
The investigation has thus far COW
cred the summers of 1923, and though
only five Of six hundred, or less than
10 per cent of the bottles have yet been
recovered, the results have warranted
the publication of series of charts
showing what Is now KIN .,yn of the
currents of the great lakes.
Most of the bottles We're picked up
on shore. OF course only the initial
and terminal points of their journey
are known, and 1t is only by COM
bining many observations that a fair
idea Of the direction taken by the float
ers has been obtained. The bureau now
groups the currents of the great lakes
Under these heads
/. All these lakes have an outflow,
and there is n slow and general set
of the water toward the outlet.
2. The prevailing winds produce a
surface current, and as these winds are
westerly they cause, il the case of
Lakes Superior, Erie ant .)nta rio, lying
nearly east and west. surface current
down the length of the lakes to the
outlets. AS Lakes Michigan and HUI
ron lie approximately north and south,
or across the direction of the wind,
the surface drift is from the west
across the lakes.
8. Then the outlets of the lakes are
comparatively small, and as all the
water driven toward them cannot pass
through. return currents are noticeable
for some distance back, and they COM
bine with the direct currents In the
wider lakes, Superior and Huron, to
make large, general whirl of the sur
fece waters. The same phenomenon Is
observed In Lake Iiichigan, which lies
across the wind.
4. The smallest cause Of motion Is
the surf, which, as soon as 1t breaks,
carries along anything that happens TO
be floating in 1t. To this motion Is due
the tendency of the bottles to pass into
deep bays and lodge at the shores near
their bottom.
A curious influence of transient na-
ture is barometric changes. A high
pressure lying over the south end of
Lake Michigan, for instance, will, by its
additional weight on the water, lower
the level under it and raise the level
northwart, making slope from north
to south. There will, therefore, be n
movement of water from the north
for time.
The weather bureau had some un-
usual assistance in the study of the
currents in Lake Superior. In Novem-
ber, 1892, the steamer Northerner jet
tisoned 1000 barrels of oil on Kewee-
nav point. A great many Of the bar
rels were finally recOvereu near Grand
MaraiS, Mimi. over two hundred miles
from the place where the steamer
stranded. The drift corresponded with
that of the bottle-papers. The work
Of investigating the lake currents will
be continued this year.-New York Sun.