383 
AMERICAN AGRICULTURIST 
saw the nail nhop up and instantly drop, you would mark 
down a - to represent E. If it touched the magnet and 
dropped, and then instantly touched it again, and re¬ 
mained in contact for a moment before dropping, you 
would mark - — to represent A, If it jumped up and 
dropped twice quickly, you would mark - - for the letter 
I. If it next touched the magnet instantaneously, then 
fell off, waited an instant and touched the magnet again, 
\nd afterwards remained off, you would put down two 
•lots with a space between them, thus - - to indicate O. 
[f it touched the magnet only once, but remained sometime 
in contact before falling off, you would put down a long 
mark, thus - for the letter L. In this manner, you 
would soon understand how to read all the letters of the 
alphabet, and the figures also. Practice would enable 
you to read a hundred words a minute. When all the 
wordi to be communicated to you are thus spelled out, a 
signal is given, and the other end of the wire can be 
closed and you open your end, and by alternately closing 
and separating the ends of the wire, you will make what- 
evei letters at the other end you desire. 
Worse's Telegraphic SEecordisig 1 Instru¬ 
ment. 
There are various kinds of instruments for recording 
upon paper the several marks indicating letters. We can 
only explain one of them in the space we have. 
Fig. C. 
In fig. 6, the wire, coming from a distant battery, passes 
around a piece of soft iron m bent upward like a horse¬ 
shoe, and called a horse-shoe magnet. Above the upper 
end of this is a bit of iron, o, upon the end of an arm or 
lever, which turns upon a pivot, with a light spring s to 
draw down the right end. Upon the right end of this 
lever is an upturned pointy. Now when the wire a is 
closed at j to send a current from the battery, m will be¬ 
come a magnet and draw down the iron bar o, upon m, 
and cause the point p to fly up, and puncture the paper 
P, which is moved steadily along by clock-work acting 
upon the rollers, r, r. If a short current only is sent, by 
simply touching the wire at j for an instant, a single dot 
will be punctured in the paper by the point p. If a long 
current be sent by holding the wires together at j, the 
pointy will be held against the paper, and mark it as it is 
drawn along by the rollers, r, r, thus-. In this 
manner, just the desired succession of dots and marks 
will be made by the person working the wire at j, though 
he may be hundreds of miles distant. A series of re¬ 
cording instruments, dispersed along a wire, will all be 
worked simultaneously by breaking and closing the cur¬ 
rent at j, or at any other place. 
Pig. 7 shows the recording instrument on a larger 
acale with the clock work for moving the paper omitted. 
Tarough the wire a coming from a distance, and b enter¬ 
ing the ground, the current of electricity passes around 
M, making a magnet of it for the instant. This draws 
down the lever A and punctures or marks the paper, here 
moved along by hand. 
Telegraphic Wires. 
These most of you have seen. In land telegraphs, they 
are usually carried along on high poles. They are fas¬ 
tened to these by glass, for the electricity will not pass 
off to the ground through glass. It travels a long w ay on 
a copper or an iron wire, rather than attempt to go 
through glass, or dry wood even ; but if there were no 
glass insulators, it would run down the poles when wet 
with rain or dew, and hasten back through the earth, to 
the other side of the battery. 
Sometimes It is desirabie to carry wires under ground. 
If this is done, it is necessary to cover them with glass 
tubes, or what is more convenient, gutta percha, a kind 
of gum which prevents the escape of the electricity to 
the soil. And this brings us to the 
Fig. 8. 
Atlantic Telegraph. 
You have doubtless read, ere this, of the long wire 
(1950 miles), or rather bundle of wires, which is now 
stretched along the bottom of the Atlantic Ocean, all the 
way from Newfoundland to Ireland; and of the fact that 
two men stand on the opposite shores of the wide and 
mighty deep, and hold instantaneous converse with each 
other. You have heard that, quick as thought, a message 
is sent from New Orleans, or St. Louis, to New foundland, 
thence as quickly to Ireland, thence across an arm of the 
sea and over England, next across or under the English 
Channel to France, and away over Europe. But on this 
wonderful feat, and the grand results to grow out of it, 
we must not dwell —at least, not now. We will barely 
stop to show you a cut or two, and describe the Cable 
that now lies way down on the bottom of the sea, far be¬ 
low the abodes of the fishes, (which, like ourselves, must 
have access to the air). There, where no living animal 
has ever gone, or will probably ever go, lies that little 
cable, through which pulsates the thoughts of two hemi¬ 
spheres. 
Figs. 8 and 10 show the full size of the cable with the 
several different parts of which it is made up. It is 
scarcely larger than a man’s little finger. We laid a five 
centpiece upon the end of apart of the cable, and it near¬ 
ly covered it. 
Fig. 9. 
Fig. 9 shows the end of the cable, and you can measure 
its size yourself. You will see that it is less than } of an 
inch in diameter. 
Fig. 10. 
Looking in the center of fig. 9, you will see the ends of 
seven little copper wires, no larger than a small pin. The 
same bundle of wires is shown in fig. 10. Seven are 
used to give greater security against any flaw in a single 
wire. These are twisted together like the strands of a 
rope, which fits them for stretching when overstrained. 
The whole seven conducting wires, put together, are 
about the size of a large knitting-needle, and through 
these the entire current of electricity must pass — the 
rest oi the cable being only for protection and insulation. 
9800 
Fig. 11. 
IS! Is it not wonderful, that these can 
.g be so covered that the current of 
-n electricity will follow out their 
2 whole length in either direction and 
g return through the earth, instead of 
r— striking out at once through the thin 
2 coating — not three-eight'ns of an 
F 3 inch in thickness? But so it is, and 
the little battery at either end will 
send its lightning current through 
the whole 1950 miles in perhaps 
less than a second of time, and 
10960 magnetize the iron signal bar at 
the other end. 
Around the conducting copper 
wire is placed three separate thin 
coatings of gutta percha, forming the 
8800 core (3) which is only f of an inch 
in diameter. The gutta percha is 
put on in three coatings instead of 
one, to avoid flaws or air holes, as 
no three of these would be likely to 
occur at the same point. So per¬ 
fect is the covering, that a current 
of electricity was sent through 2500 
miles of it with a batlery made by 
taking a 22 cent piece, (English 
Shilling), cutting a slip of zinc of 
the same size, and putting between 
them a bit of paper simply moistened 
with the tongue ! One end of the 
wire touched the shilling and the 
9400 other the zinc, and a delicate instru¬ 
ment showed that the current went 
through the whole 2500 miles of 
wire 1 
• Tarred rope is wound around the 
core as shown at (2) in fig. 10. Out¬ 
side of this, eighteen strands of iron 
12420 wire rope are wound spirally. 
Each of these wire ropes is made 
up of seven wires, each of them 
one-twenty-second part of an inch in 
diameter. 
We then have 7 conducting cop¬ 
per wires within, and 126 (7 times 18) 
iron wires as an outer protection, or 
133 wires in all; and these run 
around spirally. If all these wires 
were straightened out, and joined 
end to end, they would reach near 
ly half a million of miles — or 
nearly twenty times around the 
earth 1 
Fig. II. In this we present a pro¬ 
file of the bed of the Atlantic 
11588 ocean, along which the cable is laid. 
The figures along the side, show the 
depth of the ocean at these points. 
Thus you will see that near the mid 
ocean, the water is 12,420 feet deep. 
As 5,280 feet make a mile, it is here 
a littie over 21 miles to the bottom. 
You can get an idea of this depth 
by imagininga rope stretched out to 
a point 21 miles from your feet, and 
then thinking of this rope as let 
down from a ship. The head al¬ 
most swims at the thought of the 
deep body of water it would pass 
through. But down below this lies 
the Atlantic Cable. 
Get your maps out now, and study 
the position of the cable which ex¬ 
tends from Trinity Bay, Newfound 
and, to Valentia Bay on the wes» 
coast of Ireland. 
10980 
9500 
Note to Hoys and. Girls. 
In order to make room for the Telegraph, we have left 
over sundry other interesting things,designed for this de¬ 
partment- We are happy to announce to our young 
readers, also, that we expect hereafter to have in these 
columns, the assistance of the renowned “ Uncle Frank,” 
known the world over for his scores of interesting books 
such as “ Uncle Frank’s Home Stories ” “ Uncle Frank’s 
Boy’s and Girl’s Library,” “ Theodore Thinker’s Tales 
for Little Folks,” “ The World as It Is,” “ Stories about 
Animals,” and we know not how many more. With all 
the previous help, and now “ Uncle Frank,” and others 
yet to come in all departments of the paper, will not tha 
Agriculturist soon be “a whole team and a horse to let,” 
