The Calumet news., 1910-11-22
PROTECTION TO
LAKE MARINERS
VALUABLE DATA rs COMPLIED
MONTHLY BY WEATHER BUR
EAU IN FORM OF METEOR
ILLOGICAL CHART.

A meteorological char; Of the great
lakes has Just been received by oo-
server Cowdrick of the Houghlhon
station of the weather bureau Fh'j
innovation viii be hailed with delight
bv all captains on the great lakes ana
ali vessels owners as the purpose of
the chart is 10 tell the condition OF the
winds over the lakes during the month
for which the chart is issued. TAe
chart gives information in regard 10
coming storms. when TO expect them
how To interpret the winds and ihe
barometic pressure the magnets
variations and the meaning Of the
signals displayed by the weather bur
eau The whole chart measure aop1t
two by two and one half feet ana con-
tains a large map of the great lakes
covered with mnumerable signs, ar
rows. lines and figures denouAs tho
weather conditions
A similar chart will be Published
every month, the meteorological iata
on which win he computed from DAT
~ observations. 4 number Cf copies
OF this map will 0e received 10y On-
server Cowdrick ana given free 10
CAPTAINS and vessel owners upon ap-
plication. A number viii also be post
ed i'm frames around the town SO that
sailors and others may study them
Similar maps have been pu5lshe2
of the North Atlantic, North Pacific
Indian. south Atlantic and SQueh Pa
ci6c oceans by the weather bureau
hut this is the first map TO be made OF
the great lakes. IL is thought that
they will prove of immense benefit 10
vessel owners and captains and may
serve to prevent many wrecks. The
weather bureau collects and complies
all ocean and lake meteorological data
and desires the cooperation OF all
shipmasters. Mariners who co-oper'
ate in this work are serving their own
interests as the compiled results OF
their observations are returned TO
them free Of cost on the Mcteoroiogic-
al chart The chart represents
great deal of work. The sources Of
information on which the chart is
based cover a period from ten 10 for
" years. Numerous tables are given
showing the average depth of snow
and ice for a period of ten years at
the various stations, the character OF
the weather 10 be expected during the
month Tor each station, wind bar
ometer table, mean pressure and tenn
perature a table OF velocity, storm
warnings and other data.
The chart which gives the weather
Indications for the month of January
1911. shows that with the exception OF
the 500. Houghton had the greatest
percentaee OF DAYS of snowfall for
the month Of January than any other
stction on the great lakes for a period
covering ten years OF observations.
Storm Warnings.
Following is some Of the weatheg
bureaus literature issued f1r the ben
eft Of mariners:
The most destructive storms on the
Great Lakes are from the south or
southwest, and pass south of Lake
Superiot
All masters OF vessels before leaving
port EupAlA BDLtlu Allt ltANiHt ava 'Nt.'l'
issued by the Weather Bureau. Nod
crate 10 high on-shore winds are dan
gerOus. AS a rule, high off-shore
winds are not very dangerous as the
passage may be made under the pro-
lection Of the wiudward shore. Tho
most important consideration, there
fore, is the direction. not the velocity
Of tho wind.
The direction Of the wind ranges
from southwest tonorthwest-throu
wcst-over the Lake region. The per-
ccntage Of winds is greatest from the
northwest over Lakes Superior. Huron
and Michigan, while over Lakes Erie
and Ontario It Is greatest from the
southwest
The force Of the winds over tn,
open lakes is not very we'll determn-
ed. due 10 the absence OF observations
during January. owing to many nat
ural and artificial obstructions at th'
land stations the full force is iI
doubt. but that on the open lakes i!
calculated TO be about 1Ia times that
recorded on the land.
The weather changes are due to tn,