IMPROVEMENTS IN MEANS OR APPARATUS TO FACILITATE THE DISCHARGE OF TORPEDOES
Year: 1879

page_text: LETTERS PATENT to Donald Fergusson, of Victoria Villa, Queen's Road, Buck-
land, in the Parish of Portsea, in the County of Hants, for the Invention of
"IMPROVEMENTS IN MEANS OR APPARATUS TO FACILITATE THE DISCHARGE
OF TORPEDOES."
Sealed the 19th September 1879, and dated the 22nd March 1879.
PROVISIONAL SPECIFICATION left by the said Donald Fergusson at the Office
of the Commissioners of Patents on the 22nd March 1879.
DONALD FERGUSSON, of Victoria Villa, Queen's Road, Buckland, in the Parish of
Portsea, in the County of Hants. "IMPROVEMENTS IN MEANS OR APPARATUS TO
FACILITATE THE DISCHARGE OF TORPEDOES."
In carrying out these improvements I employ a cylindrical chamber forming an
indentation or recess in the skin of the torpedo, which recess is fitted with a piston,
which may also be hollow and of a length to admit of sufficient stroke thereto. A
small rod is provided affixed inwardly to the head of the piston, and this rod is
fitted to pass through the bottom of the cylindrical chamber for the purpose of
acting upon a lever or other suitable appliance connected with the ordinary arrange-
ment for firing by contact.
The head of the piston and the bottom of the cylindrical chamber act on a spiral
spring of regulated strength which is placed between them and surrounding the
rod.
For additional security against leakage between these parts the opening around
the cylindrical chamber is covered with thin india-rubber, over which is securely
fixed to the skin or casing a perforated shield to guard against extraneous or
accidental pressure. The air is then extracted from the chamber before mentioned
containing the spring, thereby bringing such spring into action to the extent of the
atmospheric pressure, and giving way on immersion to the indicated hydraulic
pressure at the desired depth of explosion.

page_text: The springs are to be graduated in sets ready for use in the same manner as time
fuses.
The shield having the necessary perforations clear of the area of the piston
renders premature explosions impossible.
Accuracy of fit and adjustment will ensure precision in firing being attained,
which may be further accurately determined by suspension, after the manner of
using the lead, with the addition of connection by wire and applying the piston rod
to a switch, the action of which completes the broken circuit of an electric battery
in order to afford means of indication by bell or other signal.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Donald Fergusson in the Great Seal Patent Office on the 22nd
September 1879.
:. :
DONALD FERGUSSON, of Victoria Villa, Queen's Road,. Buckland; in the Parish of
Portsea, in the County of Hants: "IMPROVEMENTS IN MEANS OR APPARATUS TO
FACILITATE THE DISCHARGE OF TORPEDOES."..
::
In order that my improvements in means or apparatus to facilitate the discharge
of torpedoes may be the better understood I have appended hereto a Drawing of
the same, of which Figure represents a section and Figure 2 a front view of parts
of such apparatus.
In carrying out these improvements I employ a cylindrical chamber a forming an
indentation or recess in the skin b of the torpedo, which recess is fitted with a
piston c, which may be also hollow and of a length to admit of sufficient stroke
thereto. A small rod c' is provided affixed inwardly to the head c of the piston,
and this rod is fitted to pass through the bottom a¹ of the cylindrical chamber a for
the purpose of acting upon a lever or other suitable appliance connected with or
forming part of the ordinary arrangement for firing by impact, and which may be
attached to the cylinder at a¹.
The head c of the piston and the bottom a¹ of the cylindrical chamber act on a
spiral spring d of regulated strength, which is placed between them and surrounding
the rod. The piston head, if elongated and hollow, would keep the spring in position
and prevent its obstructing the air passage j.
For additional security against leakage between these parts the opening around
the cylindrical chamber is covered with thin india rubber e, over which is placed
and securely fixed a perforated shield f to guard against extraneous or accidental
pressure.
The air is then extracted from the chamber a before mentioned containing the
spring & through the passage j by producing a vacuum in another cylindrical
chamber g, which is to be of proportionate size, and containing a piston / with
screw rod h¹ placed in a reverse position to the one already described. The screw
rod his operated upon by a nut h² outside the casing, on completion of which.
operation the piston h is moved the full length of the cylinder, and the india rubber
pad or ring k seals the air passages j¹, j'; a spanner applied to the end h³ of the
screw rod, which is until now kept a fixture, is then moved so as to disconnect the
projecting portion at h. The spring & is thus brought into action to the extent of
the atmospheric pressure, and will give way on immersion to the indicated hydraulic
pressure at the desired depth of explosion.
The springs d are to be graduated in sets ready for use in the same manner as
time fuses.
The shield having the necessary perforations clear of the area of the piston c
renders premature explosion from extraneous pressure impossible.
Accuracy of fit and adjustment will ensure precision in firing being attained,
which may be further accurately determined or ascertained by suspending the
apparatus in the water by a graduated line, after the manner of using the lead, with
the addition of connection by wire and applying the piston rod to a switch, the
action of which would complete the broken circuit of an electric battery instead of
the firing gear, in order to afford means of indication by bell or other signal; the
conditions of impact in both cases being equal, results would thus be arrived at not
obtainable by experimental firing.
The torpedo being self sinking it will be necessary to have the water passage i
capped or otherwise stopped until actually required for use, when it is opened, and
means are adopted to deliver the torpedo close enough to, say, an enemy's ship, the
object being its discharge by hydraulic pressure below her armour, as indicated by

page_text: the strength of the spring or springs, and at various depths, as may be determined
on before insertion.
Having thus described my Invention, and means by which the same is carried
into effect, I would have it understood that what I claim is, the arranging or com-
bining parts whereby the accurate discharge of torpedoes may be facilitated,
substantially, as described.
In witness whereof, I, the said Donald Fergusson, have hereunto set my hand
and seal, this Fifteenth day of September, in the year of our Lord One
thousand eight hundred and seventy nine.