The star. (Reynoldsville, Pa.) 1892-1946, 1908-08-26
How the Weather is FOretOld
An Elaborate System Whose Reports Grow
More and More Accurate

discussed more freelythan the wealth
er. Few on taking up their morning
papers who do not first glance at the
forecast to note the predictions for
the day. These have now come to be
SO consistently accurate that there is
no longer any surprise in the diurnal
discovery that the Weather Bureau
is right about the weather. Which
should make interesting the follow
ing dissertation on the quiet, unos-
tentatious. but certain way in which
this bureau does it's work-a work
far more important and far reaching
than would be imagined by any one
not conyersant with the subject.
The establishment of the bureau
was entirely gratuitous activity on
the part of the General Government.
1t was entirely beyond the contempla-
tion of the founders of the Constitu-
ton, and was legalized only by the
general welfare clause of the. Consti-
tuition. Begun in 1870, in conse-
quence of the growing interest in
matters relating to meteorology and
for the purpose Of giving storm warn
ings to vessels, it was at first under
the direction of the army. This ano-
maly between ships and soldiers may
be explained by the fact that upon
the Signal Corps in those days de-
volved the duty of maintaining tele-
graphic service to complete gaps in
private lines-this to the end that
the Government might have commu-
nication throughout all the States
and Territories.
Although originally designed for
the benefit of navigation alone, an
ever-broadening recognition of the
practical utility of such Service has
necessitated its continued extension
in the interest of both agriculture and
commerce. During the first twenty
years of its development the work
was conducted by the Signal Corps of
the army, under the direction and
control of the War Department, but
the demand for a strictly scientific
bureau, unhampered by regulations
of a military character, resulted in a
reorganization of the service in 1891
and the establishment of the present
Weather Bureau as branch of the
United States Department of Agricul-
ture.
How Forecasts Are Made.
To the general public the Weather
Bureau is probably best known
through the medium of its daily fore
casts and weather maps. These fore
casts are based upon simultaneous
observations of local weather condi-
tions taken daily at a. m. and s p.
M, seventy-fifth meridian time, at
about 200 regular observing stations
scattered throughout the United
States and the West Indies. Each of
these stations is operated by one or
more trained observers, and is
equipped with mercurial barometers,
| thermometers, wind vanes, rain and
snow gauges and thermometers, and
many of them with sunshine record
ers, paragraphs, thermographs and
| other devices which register auto
matically a continuous record of the
local weather conditions and changes
as they occur.
The results of the twice daily OBJ
| servations are immediately tele-
graphed to the Central Office at
| Washington, q. c., where they are
charted for study and Interpretation
| by experts trained to forecast the
weather conditions which may be ex-
pected to prevail during the follow
ing thirty-six to forty-eight hours.
A complete telegraphic report in
| cludes the following data:
Temperature pressure, precipita-
ton, direction of wind, state of
weather, current wind velocity. maxi
mum or minimum temperature since
last observation, and kind and
amount of clouds, with the direction
of their movement. From these data
| the forecaster, by comparison with
preceding reports, is able to trace the
| paths of storm areas from the tirle
of their appearance to the moment OF
observation, and approximately de-
termine and forecast their subsequent
courses and the occurrence of other
weather conditions.
| Weather services similar to that of
the United States are maintained by
the Canadian and Mexican govern
ments, and by a system of inter-
change daily reports are received
from a number of stations in these
countries. Daily observations are
also received from Honolulu, the
British Isles, Germany, France, Por-
tugal and the Azores, so that the field
represented by the daily reports ex-
tends over the greater portion of the
North American continent having tel
agraphic communication, the North
Atlantic Ocean and the west coast of
Europe.
Covering the Country.
The system for the collection and
distribution of telegraphic reports of
observations is SO arranged that all
of the principal stations in the Uni
ted States receive a. m. reports
from a sufficient number Of other sta
4 tions to represent the general wealth