IMPROVEMENTS IN TORPEDO. APPARATUS
Year: 1878

page_text: LETTERS PATENT to Charles Ambrose McEvoy, of 18, Adam Street, Adelphi,
in the County of Middlesex, for the Invention of "IMPROVEMENTS IN TORPEDO.
APPARATUS."
Sealed the 30th May 1879, and dated the 4th December 1878.
PROVISIONAL SPECIFICATION left by the said Charles Ambrose McEvoy
at the Office of the Commissioners of Patents on the 4th December 1878.
CHARLES AMBROSE MCEVOY, of 18, Adam Street, Adelphi, in the County of
Middlesex. "IMPROVEMENTS IN TORPEDO APPARATUS."
Heretofore when an assemblage of moored torpedoes has been used and it has
been desired to allow of any one or other of such torpedoes being exploded by elec-
trical means,
either from the shore or from a vessel anchored at a considerable
distance, it has been usual either to have a separate insulated cable between each
torpedo and the shore or vessel, or more generally a single cable with a number of
wires, one for each torpedo, has been led from the shore or vessel to a box or case
submerged near the spot where the several torpedoes are grouped, and from this box
or case insulated wires, one from each of the wires of the cable, have been led to the
several torpedoes. With this plan the cost of the insulated cable containing a
number of conducting wires each insulated from one another is considerable. In
order to reduce the cost of this connecting cable and to render it practicable to use
a lighter and less costly cable, I so arrange the apparatus that a cable containing a
single insulated wire only may be used between the firing point on the shore or
vessel and the box from which the branch wires are led to the several torpedoes. At
the firing point the end of the cable is connected to a make and break contact
apparatus by which by preference by the movement of a dial or pointer around a
fixed centre a battery can be successively put in connection with the wire and dis-
connected from it in a somewhat similar manner to Wheatstone's step by step dial
telegraphs.
In the box or case at the opposite end of the cable is an electro magnetic
apparatus for working a dial or pointer in unison with the dial or pointer of the

page_text: apparatus at the firing point. This dial or pointer serves as a contact maker to put the
wire of the cable successively in contact with the branch wires leading to the several
torpedoes as it is caused to turn with a step by step motion by the sending of a
succession of currents from the firing point.
As the contact maker couples up the cable with one or other of the wires leading
from the several torpedoes the current passes from the cable through the wire and
through the fuse of this torpedo to "earth," but when any one or other of the
torpedoes is to be fired, and the cable has been coupled up to the wire leading from
such torpedo, as before explained, a stronger current is sent through the cable from
the firing point to cause the ignition of the fuse. The strength of current used for
giving a step by step motion to this dial of the apparatus in the submerged box is
not sufficient to cause the ignition of the fuses in any of the torpedoes.
By this arrangement it can at any time be ascertained if the mechanism for
sending a current through the fuses of the several torpedoes is in proper working
order.
If it be desired that the torpedoes should be constructed in such a manner that
when any one or other of them is struck by a passing vessel, the fact of its having
been struck should be immediately signalled to the firing point. The dial apparatus
in the submerged box is arranged so that at one point of its revolution, which I call
the zero point, all the wires from the several torpedoes are coupled up with the wire
of the cable, and that then a constant current is passing from the firing point through
all the fuse apparatus of the several torpedoes and out through resistance coils or
apparatus to "earth." In this case if one of the torpedoes is struck, and in conse-
quence the wire from its fuse is put directly to "earth," (for doing which there are
now several well known ways) the current passes directly to "earth" without going
through the resistance. The fact of its having done so is at once indicated by a
galvanometer at the firing point, and the movement of the galvanometer may move
a contact apparatus to cause a local battery to sound a bell. The person in charge
at the firing point can then, by moving round the index or pointer herein before
mentioned, of the apparatus at his end of the cable (so as to couple up the cable in
succession to each of the torpedoes in succession) at once ascertain which torpedo
was struck, and he can then at once explode such torpedo if he desires to do so.
At the same time the passing of a stronger current to fire the torpedo may fuse a
connection in the submerged box leading to the wire which passes to this torpedo,
and so cut off the "earth" connection and leave the remaining torpedoes in proper
working order.
Or the same effect may be obtained by employing an electro magnet to switch in
a resistance equal to that of the exploded torpedo.
The improvements above described are also applicable to land torpedoes or
mines.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Ambrose McEvoy in the Great Seal Patent Office on the
4th June 1879.
:
CHARLES AMBROSE McEvoy, of 18, Adam Street, Adelphi, in the County of
Middlesex. IMPROVEMENTS IN TORPEDO APPARATUS."
Heretofore, when an assemblage of moored torpedoes has been used and it has
been desired to allow of any one or other of such torpedoes being exploded by elec-
trical means, either from the shore or from a vessel anchored at a considerable
distance, it has been usual either to have a separate insulated cable between each
torpedo and the shore or, vessel, or more generally a single cable with a number of
wires, one for each torpedo, has been led from the shore or vessel to a box or case
submerged near the spot where the several torpedoes are grouped, and from this box
or case insulated wires, one from each of the wires of the cable have been led to the
several torpedoes. With this plan the cost of the insulated cable containing a
number of conducting wires each isulated from one another is considerable. In
order to reduce the cost of this connecting cable and to render it practicable to use
a lighter and less costly cable I so arrange the apparatus that a cable containing a
single insulated wire only may be used between the firing point on the shore or
vessel and the box from which the branch wires are led to the several torpedoes
At the firing point the end of the cable is connected to a make and break contact
apparatus, by which by preference by the movement of a dial or pointer around a
fixed centre a battery can be successively put in connection with the wire, and dis-
connected from it in a somewhat similar manner to Wheatstone's step by step dial
telegraphs.
In the box or case at the opposite end of the cable is an electro magnetic appa-
ratus for working a dial or pointer in unison with the dial or pointer of the appa-
ratus at the firing point. This dial or pointer serves as a contact maker to put the
wire of the cable successively in contact with the branch wires leading to the
several torpedoes as it is caused to turn with a step by step motion by the sending
of a succession of currents from the firing point.
As the contact maker couples up the cable with one or other of the wires leading
from the several torpedoes the current passes from the cable through the wire and
through the fuse of this torpedo to "earth," but when any one or other of the
torpedoes is to be fired and the cable has been coupled up to the wire leading from
such torpedo, as before explained, a stronger current is sent through the cable from
the firing point to cause the ignition of the fuse. The strength of current used for
giving a step by step motion to this dial of the apparatus in the submerged box is
not sufficient to cause the ignition of the fuses in any of the torpedoes.
By this arrangement it can at any time be ascertained if the mechanism for
sending a current through the fuses of the several torpedoes is in proper working
order.
If it be desired that the torpedoes should be constructed in such a manner
that when any one or other of them is struck by a passing vessel the fact of
its having been struck should be immediately signalled to the firing point. The
dial apparatus in the submerged box is arranged so that at one point of its
revolution, which I call the zero point, all the wires from the several torpedoes are
coupled up with the wire of the cable, and that then a constant current is passing
from the firing point through all the fuse apparatus of the several torpedoes and out
through resistance coils or apparatus to "earth." In this case if one of the torpedoes
is struck, and in consequence the wire from its fuse is put directly to "earth
doing which there are now several well known ways), the current passes directly to
earth without going through the resistance. The fact of its having done so is at
once indicated by a galvanometer at the firing point, and the movement of the
(for

page_text: galvanometer may move a contact apparatus to cause a local battery to sound
a bell. The person in charge at the firing point can then at once explode such
torpedo if he desires to do so by coupling the cable wire to a battery of sufficient
strength to effect the ignition of its fuse.
At the same time the passing of a stronger current to fire the torpedo may fuse a
connection in the submerged box leading to the wire which passes to this torpedo
and so cut off the direct "earth" connection and leave the remaining torpedoes in
proper working order, or the same effect may be obtained by employing an electro
magnet to switch in a resistance equal to that of the exploded torpedo.
The improvements above described are also applicable to land torpedoes or
mines.
In order that my Invention may be fully understood and readily carried into
effect, I will proceed to describe more fully the manner in which I prefer to con-
struct the apparatus.
The Drawing shows a diagram view of the apparatus.
A is the instrument at the firing point on the shore or vessel; B is the cable wire
led to a submerged box situated near the spot where the several torpedoes are
grouped; C is the instrument enclosed in the submerged box; D, D, are insulated
wires led away from the box to the several torpedoes, there being a separate wire
for each torpedo.
Each of the wires D is coupled to one or other of a series of metallic contact
pieces E ranged in a circle round the axis of a metallic pointer F which can be
turned with a step by step motion and successively brought into electrical contact
with the several contact pieces E. The axis of the pointer is in electrical commu-
nication with the wire of the cable. The wire from the cable is first led to the coils
of an electro magnet G, and thence passes to the axis of the pointer. H is a mag-
netic armature in front of the electro magnet G; when a positive current of sufficient
I strength is sent through the cable the armature is rocked in one direction, and when
a negative current is sent it is rocked in the opposite direction. From the armature
motion is transmitted to a pawl which works into the teeth of a ratchet wheel on
the axis of the pointer F, so that by sending a succession of reversed currents of
sufficient strength through the cable the pointer F is turned with a step by step
motion and is successively brought into electrical contact with the several contact
pieces E.
In the instrument at the firing point a is a handle, by the turning of which a step
by step motion is given to the pointer of a dial b and a simultaneous movement to
the pointer F of the instrument C in the submerged box. When the handle a has
made a half turn it couples one pole of the battery to the cable and the other to the
earth connection, and when it has made a complete turn the connections are reversed.
The pointer of the dial b then moves forward from one division of the dial to the
next, and simultaneously the pointer F is turned in unison with it. The operator
at the firing point can therefore always see which of the torpedoes is in electrical
connection with the wire of the cable, and he can test each torpedo in succession by
moving a handle, say, at h, to cause the current passing back from the torpedo
to pass through a galvanometer at e, and by the movement of the needle of the
galvanometer it can be seen whether the resistance of the circuit through this torpedo
is in its normal and proper working state.
When the pointer of the dial b is brought to zero, or as it is marked in the
Drawing to "signal," then the pointer F of the apparatus C is in electrical com-
munication with a contact point which is coupled to all of the branch wires D, and
usually the apparatus is left in this condition, the handle a being then locked and
prevented from turning by a bolt actuated by a handle at G.
The current from the battery at the firing point then passes to earth through the
resistances in all of the torpedoes. If now any one or other of the torpedoes is
struck by a passing vessel and the wire from its fuse put directly to earth, so that
the current passes freely to earth instead of having first to pass through the resist-

page_text: ance, the fact of the current passing freely to earth is notified at the firing point by
the movement of the needle of a galvanometer d; the movement of the needle of this
galvanometer effects an electrical connection by which a small battery is caused to
sound a bell at c. The operator at the firing point can then if he pleases at once fire
the torpedo that has been struck by moving a handle at f and coupling up, to the
wire of the cable a battery of greater strength, the strong firing current will pass to
earth through the fuse of the torpedo that has been struck, and will ignite this fuse,
but will not effect the fuses of the other torpedoes as to pass through these fuses, it
has also to pass through resistances which impede its passage and reduce its strength,
so that the portion of the current which passes to earth through them is not of
sufficient strength to ignite the fuses.
When the fuse of any one or other of the torpedoes is exploded by the passing of
a strong firing current through it, the wire leading from the box C to this torpedo
is simultaneously cut off from electrical connection with the contact pin E to which
it was previously connected, and this pin is put to earth through a resistance either
somewhat greater or less than the resistances in the torpedoes, so that the firing of
one or more of the torpedoes does not interfere with the power of being able to turn
the pointer F of the apparatus C in unison with the pointer of the dial b.
Afterwards the operator at the firing point can ascertain which of the torpedoes
has been fired by passing the pointer of the dial b to each of the divisions of the dial
in succession and ascertaining by the galvanometer e the resistance of the circuit
through each of the torpedoes, so that he at once ascertains which torpedo has been
put to earth through the greater or less resistance.
The cutting off of the wire D from its contact E when a strong current is passed
through it may be effected by the wire being coiled around an iron core forming an
electro magnet, which when a strong current is passed through the wire is of
sufficient strength to shift the position of a contact apparatus and then effect the
required alterations in the connections, but which is not of sufficient strength to
effect any change when the weaker currents used for the signalling and testing
operations are passed through the wire.
It will be evident that with the above described apparatus any one or other of
the torpedoes can if desired be exploded by the operator at the firing point whenever
he desires to do so. To effect this he would by turning the handle a bring the
pointer of the dial b opposite to the division of this dial; that would indicate that
the cable had been brought into electrical communication with the torpedo required
to be exploded, and then when it is ascertained by previously adjusted sight points
that the vessel is above the torpedo he can fire the torpedo by passing a strong
firing current to the cable.
In this way the apparatus can be used for firing any one or other of a group of
sunken torpedoes, or if the torpedoes are buoyant ones they need not be fitted with
apparatus for putting the wire from their fuse directly to earth whenever the tor-
pedo is struck by a passing vessel. The same arrangement of apparatus can also be
used for firing any one or other of a number of mines or torpedoes on land and for
separately testing the firing mechanism of each mine whenever desired.
Having thus described the nature of my Invention and the manner of performing
the same, I would have it understood that I do not limit myself to the precise
construction of the apparatus as above set forth with reference to the Drawing
annexed, as the form of the apparatus and its details may be greatly varied, but I
claim,―
First. The combination of apparatus, substantially as herein before described,
whereby any one or other of an assemblage of torpedoes can be tested or can be
fired by the passage of an electrical current through a single wire cable passing from
the firing point to a spot near to the group of torpedoes and from whence branch
wires are led to several torpedoes.
Second. The combination of a group of torpedoes with wires leading to a sub-
merged box from which a single wire cable passes to the firing point, the submerged
box having within it apparatus by which the wires from the torpedoes can by the

page_text: passing of electric currents through the cable be put in succession in electrical con-
nection with the cable to allow of their being separately tested or fired at will.
In witness whereof, J, the said Charles Ambrose MoEvoy, have hereunto set
my hand and seal, this Thirty first day of May, in the year of our Lord
One thousand eight hundred and seventy nine.
C. A. MCEVOY. (L.S.)