American union. [volume] (Morgantown, Va. [W. Va.]) 1855-1859, 1857-08-07
From the London Ntcs, yuiy7.
Tho Atlantic TELEGRAPH,

every reason to believe that by the end
of this month the Agamemnon and Nj
agara will have commenced depositing
in the Atlantic tho cables which will, it
is to be hoped, cement the amicable,
political, and commercial relations of
England and the United States. Both
these vessels are far advanced in the
work of shipping the cable, one at Biz.
kenhcad, where Messrs. Newall & Co.
are under contract to supply one-half
the entire length, and tho other below
Greenwich Hospital, where the other
half is being supplied from the works of
Mcssrs. Glass, Elliott, & Co., of East
Greenwich. Each firm has undertaken
to furnish twelve hundred and fifty
miles, and the total distance from shore
to shore being 1000 statute miles, there
will Of course be surplus of 600 miles,
a margin which is believed to be amply
Sufficient to provide for all cxigencies
and contingencies which it is reasona-
bic to anticipate.
X
AS already intimated, the total guam
tity of cable to DO received is 1850
miles. Each coil at the centre forms
length of about ST miles, and the
weight of the cable is about one ton
per mile. 1t is expected that the whole
of the cable will be on board by about
the goth inst, and that by tho 23d or
the 18th the Agamemnon will be on
her way to Cork, where she is to Join
the Niagara. The precise course then
to be pursued as regards the paying out
OF the cable by the two vessels is not
yet determined. Much, Of course, must
depend upon wind and weather, and
provision will doubtless be made for all
the contingencies which wise foresight
and the concurrence of the most expo
rienced heads can anticipate.
The operations of Greenwich are un-
der the active superintendent of two
of the greatest electricians of the day,
DR.. Whitehouse, of this country, the
chief electrician of the Atlantic Tele-
graph Company, and Professor Morse,
of the United States. These gentle.
men are both doing all in their power
to insure success to the enterprise
| They are in constant communion with
each other, and their intercourse will
no doubt be as beneficial as regards
the advancement of telegraphing in
general as it is imperatively necessary
to meet the new and extraordinary re-
quircmcnts which have sprung out of
the pending experiments. Iu further
ance of this object DR.. Whitehouse has
been for some time engaged in making
interesting Investigations with regard
to the time occupied by the transmits
sion Of electrical currents for immense
distances i'll the ocean, and he has in
vented scrutinizing agent which at
once ascertains differences and places
the result on record, so that they can
be examined and compared and made
the basis of future discoveries and i'm.
| provements.
The basis Of this instrument is n rib
bon of paper, chemically prepared, I'M
rolled from o drum. An application
of Professor Morse's printing machine,
which with the aid of local batteries,
imprcsses marks on the ribbon; and a
second pendulum, whose vibration
transmits an electrical current in oppo-
site directions along the wire at each
beat or semi beat. The effect of the
process is that there are three parallel
rows of marks impressed on the surface
of the paper--the innermost represent.
ing the home signal, the next the dist
ant signal, and the third the seconds.
From the relative position of the marks
may be learnt the velocity Of the sew
oral currents and the interval between
each, and the main objects of the cxpe-
pcriments, which are entirely novel,
having arisen out Of the special require
ments or the Atlantic enterprise, is of
course to diminish the period necessary
for exchanging signals.
In connection with this point, it may
be remarked that DR.. Whitehouse has
actually devised mode of weighing
electrical currents. Hitherto there has
| been no means whatever Of ascertaining
this. All that could be said of par
ticular current, so far as it's force was
concerned, was that it was slight or
considerable, as the case might be. BY
means Of this wonderful invention, a
current, after it has travelled thousand
miles, may be weighed with the utmost
nicely, on achievement which can
hardly fail to be attended with the most
important consequences in connection
with the extension Of submarine COM
munication.