El Paso herald. (El Paso, Tex.) 1901-1931, 1910-05-27
THE recent controversy between the

THE recent controversy between the
weather bureau and the hydro
graphic office as 10 which should
publish the weather charts of the seas
has brought into notice one Of the most
interesting establishments in the entire
government service. While il is not
the purpose of this article to determine
which bureau had the best of the argu-
ment before congress, since each claims
the victory, the fact remains that each
is doing a work that might be done by
one.
The weather bureau asserts that it's
intercollegiate are the men best fitted
to carry on the weather Investigations
of the seas as well as those on the land
and that properly to invests gate world
weather conditions it is NECESSARY that
it's inquiries shall cover the seas and
the land and that therefore the weather
bureau, if it is 70 attain to the full pos
sibilities of its usefulness, must CON
slider the weather of the globe as a
whole.
Pilot Charts)Necessary.
The photographic office replies that
careful and accurate pilot charts are alb
sOlutely essential to safe navigation.
and that too many lives and too much
treasure is dependent on such charts TO
entrust -heIr preparation to a bureau
which is n0t sLpT CSed to know about
navigation anil the dangers of the seas,
AMI which was founded for the purpose
oc supplying information about weather
conditions 20 the farmers of the country
1t adds that naVlcatcIs everywhere pre-
fer the photographic pilot charts TO
these Of the reather bureau
But aside from this controversy over
the publication of pilot charts the by
geographic office is peculiar and Valu-
able institution. 1t has been stated in
IL; al Dit til.
GERS that the photographic office of the
United States renders greater AID To the
navigatOrs of the world than any SINH
lar bureau in existence, not even ex-
ceIt that of England itself
Must "knOw the Ground
If armies are TO be handled with in
telIigence and success 1T is essential
that the ground over which they are to
maneuver shall be well known to their
commanders. By the same token if
navies are 10 be safely handled their
field of action must be gone over care
fully and plotted. While the hydro
graphic office cOnferS intestimable benz
fits upon the merchant marine of he
world, in the last analysis its purpose Is
to have the oceans so mapped that our
mighty sea dogs can be handled TO ad-
vantage and with safety should we be
called upon to unleash them for an in
terna tiOnal combat.
The work of producing navigatOrial
charts from start TO finish is carried
on with degree of accuracy that is sur
prising to the uninitiated. The first
thing that must be done is to make a
survey or the harbOr to be charted.
After general inspection of the harbOr
is made a base line is run, and to the
resulting survey this base line is as i'm
pOrtant as the keynote TO a musical
composition. Let it be Inaccurate in
the slightest degree and the whole sur
vey is thrown out of keller.
The Instruments.
base line may be a mile dong and
yet not vary a fraction of an inch in its
measurements. Steel tapes are used for
measuring. They first have been tested
at a given temperature at the govern
ment bureau of standards in Washing
ton, and even the expansion or cOntrac-
ton through heat or cold has to be al
lowed for in order that the measure
ment may be exact. With this line as
the key of the survey, by a process of
triangulation and trigonometric caIcu-
lations, other distances are determined,
and every feature of the landscape that
might serve as an aid in determining
location by the navigator is set down in
its exact location by the surveyors on
the rough charts they make as they go.
After the surface appearance are care
July translated INTO map FORM, sound
ingS are taken to develop the depth of
the water at every point in the harbOr.
These soundings are taken with great
care. and in vast numbers. so that I'M
der the most eXacting conditions imag-
Unable the navigator may know exactly
how much water his ship is in at any
given instant. They are made at low
tide. so that ne is always on the safe
side of error.
Making the Map.
When the survey is completed, the
next step is to transfer the rough charts
and the field notes to a map sheet, and
when the map maker gets through with
his task the resulting map means every
thing to the navigator. All details es-
sential for him TO know about the har-
Dor under study is there laid down.
After if 1t finished ii is turned over TO
the proof reader, who examines it for
every possible error. So many things
are to be considered that he reads" his
map by schedule, and when he is
through with the task. the marks indi !
cate that even tn expert map maker can
make mistakes. After these are cor
rected the map goes to the engraver, to-
gether with a copper plate that has been !
finely Furnished and upon which the
projection has been made according to
the general computation. No engraver |