Evening times-Republican. [volume] (Marshalltown, Iowa) 1890-1923, 1900-11-17

study and competition has resulted In
Improved forecasts, 20 that mariners
universally heed the storm warn
ings, horticulturigts and truck garden
ers make ample provision againet frost,
shippers Of perishable produce give
full credence tosthe cold-wave predic-
tons. OF the West Indian hurricanes
which have swept our Atlantic seaboard
from Florida to Maine during recent
years not one reached a single seaport
without danger warnings having been
sent we'll in advance of the storm, and
unnecessary warning has been issued.
The result is that no disaster OF conse-
quence a occurred. Large owners Of
marine property estimate that one Of
these severe storms traversing our At
lantic coast in the absence Of danger
signals would leave not less than 3d.
100000 worth OF w~reckage. On two oc-
casions a census was taken Immediately
after the passage of severe hurricanes
TO determine the value of property held
IN port by h danger warnings sent out
In advance of the storms. In one case
the figure was placed at 1874, 900, 900; In
the other, at $38, 900, 900. OF course this
ldoes not represent the value Of property
saved. 1t simply shows the value Of
property placed in positions OF safety as
q result Of danger signals and warning
messages sent to masters. On Jan. /,
1898. an extensive cold wave swept from
the Rocky m%ountains eastward to the
j~seaboard. Estimates secured from chip
Ipers in 100 principal cities indicated that
property valued at $1,000, 900 was saved
as a direct result OF the predictions sent
out.
There is hardly a daily paper that
does not publish weather forecasts in a
prominent place, and there is scarcely
q reader who fails to note the predic-
tons. The utility OF these forecasts to
the agriculture, the commerce, and the
industry OF the country is SO great that
At may be interesting to note more in de-
tall the methods by which observations
are collected. forecasts made and mete-
iorological information disseminated.
Our weather bureau maintains about
2OO regular meteorological stations each
In charge of a trained observer. adyan-
|tageously located geographically for the
taking OF observations. The transmits
sion OF reports is accomplished with re-
markable rapidly by means OF an ef-
tective arrangement of Geographic cir
cults. Observations from all parts Of
the United States and Canada, from the
Atlantic to the Pacific, are collected al
Washington within thirty minute ar
ter the observers have read the station
Instruments and filed their observations.
charts are prepared in the CEN
tral o1lces at Washington and Toronto.
and at many of the large stations al
which reports are received; and by Q
o'clock (seventy-fifth meridian tima) the
charts are complete. The char Of
greatest value to the ~forecaster contains
Tor each station the temperature. bar.
lometric pressure, wind direction and ye.
locl1y, weather conditions whether
raining, showing, cloudy, partly cloudy,
or sclear-andt the amount of precipita-
ton, y any. Lines called .isobars." are
drawn Tor each one-tenth OF an inch ii
pressure, bounding the area
over which the air is respectively light
eet n heaviest. These areas are called
highs and lows" but they are onlv
relative terms. as on one map the high.
est pressure may be over two inches &
excess Of the lowest. while on he man
5of another day the difference NAV Is
less than one inch.
evera other charts are nren.raa /,
q forecast room of the central Once
az washington. as follows: Temnera-
ture-change map. showing the maxi
mum and minimum t,,ra az aaal
station, With changes from the da,. Ia.
Tore and changes from the normal. No.
5ometer-change map. showing tu.slrasa,
t~wenty-four hour changes and oha.aa1
from the normal; cloud map. indicatin
~, el1aiacter, nomenclature, quantity,
ana movement of clouds; and 4 man
SAVING Wet-bulb and dry-bulb tenper.
atures. with differences bet waan -
two. cue
= the student OF the weather m.ns
VII payselose attention to them each
uay, ne VIII find that the highs and 1--we
80 acloss the country in almost rer1,.
81 succession. II the high be a dacidad
~ VIII a TERRITORY
s NO thousand miles in width. ths
Weather within IT'S influence will ha coId
ana ciear, and the winds will have =
genera tendency spirally outward from
me center In a direction c~orrespondino
y the movement of the hands Of :
Wa1ch. The low is the opposite ~ ,bs
nlgn In almost all its charaotaris*io.
4 as usually attended by clouds. rain
or snow. and high winds. The winds
Within the influence of the low blou
splrally inward in a direction cnntr.r j,
70 rnose nder the influence Of the hipb.
lower the barometer n the stasn.
er the gradient. the more rapid NJ
Wh1rl. These are some OF the 4 arac
terfsttcs OF lows. Those OF like ola g
a nearly the same course. and nro.
duce about the same results: bu, thav
DO not always move with the same
rapicity. No exact rule in regard "a
them a be laid down. Empirical
reasoning, mi intimate association
with the charts, day after day and
year after year. in the main equip thu
, ueessaau foTeas'er for his importan,
Just as the eddies in a river 60 whirl.
ing down stream. so are cold-waye ed
dies (highs) and rainstorm eddies
Qows) carried eastward by the genera
movement of the upper atmosphere II
the ATTITUDES of the United States. n L
important that the fundamental princi.
Pies OF hese eddies be understood. since
the weather changes experienced from
day to day depend almost wholly upor
the development and drift of these
high-pressure and low-pressure eddies
or. as they are better known. highs and
lows. The two eGdies are easily dlstin.
guishable the one from. the other. for
while ira yal{pr "a G u-, NJ IL 49,