The New York herald., 1874-12-02
Scientific Work of tho Bureau of Navi-
Ration-The Surveys in the Pacific
and observation-disclosures Achieved
The Panama Canal.

gation-The Surveys in the Pacific
and observation-disclosures Achieved
The Panama Canal.
WASHINGTON, Nov. 90 1874.
Commodore David Ammen, Chief of the Bu.
reau OF Navigation, Navy Department, in his an
nual report to the Secretary OF the Navy, says
that the liquid marine compass has been found so
superior that 1t is adopted for all purposes. A
sufficient number OF dry marine compasses has
been retained for any sudden emergency, and the
others Will be sold. Bronze binnacles, "compass
stands" are being subs tituted in lieu OF wooden
ones. The photographic work, especially on the
coasts OF Mexico has been satisfactorily prose-
cuted. The survey OF the exterior coast and Gulf
OF California has been almost completed ana q
running survey completed from our boundary
the Rio Grande, to Yucatan. Very considerable
errors OF latitude and longitude have been
corrected. Our vessels or war at va
rlous points have done useful work. especially
the Wasp in the mouth of the Rio de la Plata. The
longltudes IN the West Indies and Central America
are being rectined.
The purchase OF two three -masted schoOners
and the employ yment OF one steam vessel, all prop
erly fitted out is regarded as necessary to q
proper prosecution OF the survey OF the North
Pacific Ocean. The aggregate results OF vessels
acting In concert are much greater than when
acting singly. 1t Is supposed necessary for us to
survey the North Pacific, as well for q proper re-
turn to other Powers Tor their exertions In other
seas, an appreciation OF our national interests.
The interOceanic canal sHrveys have been iabo-
riously pursued and their results are gratifying,
and probably point to the commercial possibility
OF the construction OF ship canal. The deep sea
sOundngs have been most successfully prosecuted
by the nse OF steel wire instead Of hemp line. The
steel wire Is relatively much lighter compared with
the attached weight to sink it. 1t has neither the
elasticity or .stretchn nor the surface friction"
OF hemp line, all elements that tend to make the
results more reliable or, within reasonable limits
OF error, entirely The ease with which wire Is
protected from deterioration, It's portability and
small cost are other advantages making 1t pos
slDle for all vessels OF war to be provided with
sounding apparatus without interfering In any
degree with their other duties. Twelve sounding
apparatus are now ready for use as may be re-
quired by the department..
The ''running llghts' Of sailing and steam ves-
sells are supposed to be detective ior reasons as
signed and common to all nations. Experiments
are In progress to ascertain whether the
as to the means OF correction. An electric lignt
mas been purchased and Will be employed In ex-
perimentai signalling. 1t Is found that the light
can be produced without delay aud with certainty
OF vessel Of war, and II found advantageous 10
supply IL to other vessels as the Appropriations
Will warrant The chrome. .semic system OF sig
Mailing Will be tried fu1ther.
1t has not so lar proven satisfactory, pc rhaps on
account OF detective appliances or apparatus.
recommendation Is made to require young
oflcers passing lOr promotion to be well versed In
the army method OF signaling.