The herald and mail. [volume] (Columbia, Tenn.) 1873-188?, 1875-09-17
sOundings in the Gulf of Mexico.


Blake, Lieutenant Commader @. D.
Sigsbee commanding, has recently re-
turned to Washington, after an excel
lent winters work in running lines of
soundings in the Gulf of Mexico. These
deep sea examinations are the first ever
made in that portion of the ocean, and
consequently, in points of novelty, are
on par with those of Commander
Belknap of the bed of the Pacific.
Steel pianoforte wire, No. % gauge and
weighing but IA! lbs. to the mile, was
employed as sounding line with uni
form success, even in heavy seas.
The result show that the slope of the
delta OF the Mississippi is gradual, and
that the deepest water in the vicinity is
on prolongation of the axis of South
Pass. At the end of that line, 100 miles
distant from South Pass lighthouse, the
depth was l, 632 fathoms. The limiting
lines of the system of lines, which was
run by the Blake, extend (magnetic)
east, half mile south of Pass rOutre,
at the end of which was found 1876
fathoms, and southwest of Southwest
Pass, which ended in COS fathoms. On
the latter line was found the only alb
rupt irregularity of the bottom found
off the delta. Up to April, the currents
Immediately off the passes set generally
to the westward, after which they ap-
peared to set gradually to the eastward.
On May 4, the Blake commenced line
between Southwest Pass and the Rio
Grande. Until half the distance be-
tween the ends of the line had been
passed, the depths were not great ; but
afterward the water deepened, the
greatest depth on the line being 900
fathoms, About 105 miles from the
Rio Grande, at seventeen miles from
the Southwest Pass lighthouse, the
water had deepened to 80 fathoms, after
which it shoaled gradually to as little
as Is fathoms, and 80 fathoms was not
reached again until ninety-four and a
half miles from the lighthouse.
On May a sounding was got in At
fathoms, the sounding rod bringing up
hard bOttom-enameled shells, etc.
(the only instance in which hard bot
tom was obtained during the season
Tortugas was neared). at sounding
in 583 fathoms, in latitue27 deg. min.
north, longitude 81 deg. IS min. Is Sec.
west, the sounding rod brought up dark
mud, or ooze, which emitted so often
sive an odor as almost to drive the
people from the forecastle, where the
sounding operations are carried on.
The edor soon passed away.
On May 8 commenced the longest
line run during the season, that from
the Rio Grande to Tortugas, a distance
of about 76O miles 100 fathoms was
not reached until about forty miles
from the Rio Grande; the water then
deepened rapidly. At about 100 miles
from the Rio Grande the depth was
S39 fathoms, whereas the previous and
following soundings were respectively
1887 fathOms and 1,648 fathoms. This
was the only marked popularity of the
bottom found on the line; soundings
varied from 1 900 to 2, 100 fathoms, the
bottom being undulating, apparently.
No northern extension of the bank of
Yucatan was discovered. The greatest
depths were zoos fathoms, 2,O25 2,016
fathoms. and 2,119 fathoms. The
average specific gravity of the water OF
the Gulf is about l. 0265.
The following is IN example of the
quickness with which the Blake does
her work: On one occasion she got
the following results in actually one
hour from the time of stopping the
engines to sound to the time of steam
ing ahead again: A sounding in l, 500
fathoms, with specimen of the bot
tom, water specimens, and temperature,
at the surface and at the following
depths in fathoms 100, 300, 600, 900,
1900, 1900. There were but seven
on the watch to accomplish this.
During the summer the Blake will
work in the Gulf of Main, when the
new machine will be tried. as also
new sounding rod by Admiral Porter,
and another by Mr.. Wilson of the navy
yard. american.