Evening star., 1894-03-07
NOVEL INVESTIGATIONS
Determining Great Lake Currents BY
Means of Floating Bottles.
Interesting Report From the Weather
Bureau-HOw Information Was
Received-Three Currents.

An interesting report on the currents
OF the great lakes has been submitted to
the Secretary of Agriculture by Mark w.
harrington, chief of the weather bureau
The investigation which resulted in this
report was suggested by observation of
the accumulation of wrecks and wreckage
at certain points and along certain por-
lions or the shores Of the lakes. The in
Vest1gation was made by means Of bottles
containing instructions from the bureau
ana constructed so as to float in the water
for an indefinite period. These bottles were
sent to masters OF vessels engaged in traf-
fic in the great lakes, light house keepers,
&c. with the request that they be thrown
into the water after the paper in the bottles
had been marked with the time and place
of fioating and with the name of the per-
son who consigned each to the water Within
the bottle was also placed a franked en-
Velope addressed to the weather bureau
and instructions requesting the finder to
indicate the time and place Of 1nding and
send the blank filed out TO the bureau.
The report, with a number of valuable
maps, showing the lake currents was made
up from such of these blanks as were re-
turned.
The investigation covered the summer
seasons of 1892 and 1893. 1t was found
impossible to make any valuable deductions
from bottles tioated in the autumn and
1t was aScertained that there were fOur
general currents to be observed in all the
lakes. The outflow, toward the outlet of
the lakes, u continuous current effecting
the entire mass of water and proceeding
slowly, with a perceptible reactionary fiow
resulting in more or less of a circular cur
rent around the lakes; a surface current
due to prevailing winds and consisting CT
a mass of water driven before the wind
and including also a return or reactionary
current caused by the flow into depths
made vacant by the action of the winds;
return currents. and finally, surf notion
The most important current is the sur
face flow caused by the wind. 1t is a maxim
along the lakes that the wind will blow in
the direction in which the current was
running from six to twelve hours before
the wind begins. This maxim is an old one
dating long before any investigation, but
it is fully explained by the result of the
observations taken.
The report includes exhaustive tables con-
cerning the prevailing winds over the great
lakes
Much difficulty was encountered in at
tempting to discover the velocity of the
various lake currents, but in general they
are supposed to run at rate of from four
TO twelve miles a day. There are certain
currents which have, at special seasons OF
the year. been observed to run at a much
greater velocity, but no general law con-
cerllng these have as yet been discovered
The number of blanks returned was only
about 10 per cent of the total number sent
out.
Many CT the blanks were returned with
great care. some from the shores of Cam
aua as well as from the states. All were
promptly acknowledged with view to in
creaslEg, by every means possible, the per
cent Oh blanks returned to the bureau.