IMPROVED ARRANGE- NULLIFYING OR THE DESTRUCTIVE MENTS FOR ACTION PREVENTING TORPEDOES AND SUCH LIKE EXPLOSIVE AGENTS UPON SHIPS OR VESSELS
Year: 1877

page_text: LETTERS PATENT to Duncan Mac Ivor Campbell, of Loch Gair House, in the
County of Argyll, North Britain, for the Invention of "IMPROVED ARRANGE-
NULLIFYING
OR
THE DESTRUCTIVE
MENTS FOR
ACTION
PREVENTING
TORPEDOES AND SUCH LIKE EXPLOSIVE AGENTS UPON SHIPS OR VESSELS."
OF
Sealed the 18th January 1878, and dated the 9th August 1877.
PROVISIONAL SPECIFICATION left by the said Duncan Mac Ivor Campbell
at the Office of the Commissioners of latents on the 9th August 1877.
DUNCAN MAC IVOR CAMPBELL, of Loch Gair House, in the County of Argyll,
North Britain. *IMPROVED ARRANGEMENTS FOR PREVENTING OR NULLIFYING
THE DESTRUCTIVE ACTION OF TORPEDOES AND SUCI LIKE EXPLOSIVE AGENTS
UPON SHIPS OR VESSELS."
This Invention mainly consists in arrangements for protecting ironclads and their.
crews from wholesale destruction by torpedo action.
The extreme rigidity of great ironclads doubtless gives intensity to the stroke of
torpedo elements. It seems equally clear that such intensity would be greatly
diminished or exhausted in contact with yielding elastic substances.
According to my Invention I apply to or cover our present armour plating, so far
as it is exposed to torpedo action, by a close-fitting elastic shield or coat of the
substance known as india-rubber or gutta percha, manufactured specially with the
most suitable amount of elasticity combined with resistance, incorporated with
numerous air chambers, the additional elastic properties of which, under extreme
pressure, will be a powerful repelling agent.
The means by which
attach this massive coat securely to the bottom and sides
of the ship is, for example, thus:-
First. It is intended that this shielding or armour coat shall be manufactured in
separate pieces or strips of convenient breadth and lengths, equal to the distance
from the garboard or keel to the water line, or as much above or below it as may be

page_text: desirable, the breadth being, say, four feet, more or less. These lengths are each to
be incorporated (in addition to air chambers) with chain or wire braces reaching
from top to bottom, equidistant; the ends of these strips, above and below, including
wire ends, to be firmly bound with suitable iron cappings, the lower ends being
secured to the ship's keel, close to the garboard, the upper ends to be drawn round
the bilge and side to the intended elevation, where in a tapered form same shall he
attached to suitable apparatus for raising it by screw or other power, until the
whole piece from keel to top shall be firmly pressed to the ship's bottom and sides,
the incorporated chains or wire braces bearing the chief, if not entire strain.
Successive strips being placed close to each other throughout the ship's length will
add no weight; its great floatage power may call for more ballast, as the ship will
be more buoyant.
In case of injury to any portion of the armour it can be removed and replaced, and
its toughness and elasticity will cause the expansive force of the great explosive to
escape by unheaving of the superincumbent water; and, further, I benefit by its
exhaustion by a continuous depression of the elastic shield over an extended
area.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Duncan Mac Ivor Campbell in the Great Seal Patent Office on the
9th February 1878.
DUNCAN MAC IVOR CAMPBELL, of Loch Gair flouse, in the County of Argyll,
North Britain. IMPROVED ARRANGEMENTS FOR PREVENTING OR NULLIFYING
THE DESTRUCTIVE ACTION OF TORPEDOES AND SUCHE LIKE EXPLOSIVE AGENTS
UPON SHIPS OR VESSELS."
The present elaborate system of defence by countermines has of necessity become
a distinct service, with special training and equipments, nevertheless liable, from
many unavoidable causes, to miscarriage. In this view propose to substitute what
I believe would be a simple, self-acting defence, more direct, less costly, more
reliable, and always in position.
The extreme rigidity of great ironclads doubtless gives intensity to the stroke of
torpedo elements; it seems equally clear that such intensity would be greatly
diminished or exhausted in contact with yielding elastic substances. On this basis
it is proposed that our present war ships shall, so far as exposed to torpedo
action, be covered by a close-fitting elastic shield or coat of the substance known
as india-rubber or gutta percha, manufactured specially with the most suitable
amount of elasticity combined with resistance, incorporated with numerous air
chambers, the additional elastic properties of which, under extreme pressure, will be
a powerful repelling agent.
The means whereby it is proposed to attach this massive coat securely to the
bottom and sides of the ship are in substance as follows:-
First. This shield or armour coat should be manufactured in separate pieces or
strips of convenient breadth (say, four feet, more or less), and in lengths suited to
requirements in relation to the ship's structure, these strips to be each incorporated,

page_text: in addition to air chambers, with five wires or small chains, more or less, reaching
from end to end, equidistant. The introduction of bilge keels makes it necessary,
so far, to restrict the length of lower strips to the spaces between said bilge keels, the
wire or chain ends of each strip at top and bottom to be duly strained and secured to
the keels between which they are placed; the top strips, based on the upper port and
starboard bilge keels, to be carried up to their proper elevations and there connected
with straining apparatus, as shown in the accompanying Drawings, or otherwise,
successive strips to be so fixed throughout the ship's length covering the whole area
requiring such protection. The pliancy and elasticity of this enduring coat will
readily accomodate to the ship's curves under pressure of floatage, displacement, and
other agents. This shield will not appreciably add to the weight; its great floatage
power will admit of additional equipments or more ballast, and will make the ship
more.buoyant.
Simple arrangements can, if desirable, be made for the appliance of air pumps
for inflating or collapsing air chambers, and thereby so far adjust the ship's
immersion or displacement as affecting pressure on her engines and relative
speed.
In the event of any injury to any portion of the shield, the injured strip or
can be easily removed and replaced by sound ones.
strips
It is believed the extreme
toughness and elasticity of the shield will exhaust the expansive force of the great
explosive. Possibly some advantage might be gained by converting the present
extra bottom and water-tight chamber into the elastic principle of the shield. It is
difficult to imagine a case in which a ship could do down with such a coat.
In the event of injuries that would otherwise cause serious leakage, it would
become an efficient stauncher; if so, the cost and encroachment of cellular
construction might be avoided.
It may be considered that the time has come when ships of war should he
integrally impervious to submarine explosives, at whatever inconvenience, disregard
of symmetry, or otherwise. There can be no doubt that a certain thickness of
suitable resisting material can, however, be made to fix the limit of torpedo force,
and that such thickness can be ascertained by experiment; in the meantime a
possibly efficient depth of shield is presented in the accompanying Drawing, in the
conviction that exploded forpedo Huid will instantly radiate over a wide area,
wedging its way between the yielding surface of the shield on one side and incom- -
pressible water breast on the other, thus extending its area until exhaustion shall
ensue; in this view unheaving of water is not anticipated, the shield offering no
fulerum for such exertion. How far this shield may be applied above water for
neutralizing the force of shot, and to such extent reducing weight of armour plates,
is worthy of consideration: and, further, whether the said shield can be applied in
a much lighter form to passenger ships and others as a means of saving the ship
and all it contains in cases of heavy straining or other injuries that so frequently
result in the report" foundered at sea with which the world is too familiar. The
single case of the President passenger ship may be briefly noticed: Last seen
labouring heavily in a seaway," after which no traces of her ever appeared.
DESCRIPTION OF THE DRAWINGS, ILLUSTRATING HOW THE SAID INVENTION IS TO
BE PERFORMED OR CARRIED OUT IN PRACTICE.
"
Fig. midship section of war ship.
Fig. 2. view of portion of one strip, front section of shield; Fig. 8, side section of
same.
In the said Drawings, A is fighting trim of ship or vessel: B. sides of vessel; C,
lower edge of armour plates; D, double bottom (water-tight): E, elongated bilge
keels: F, original bilge keels; G. vertical teak planking: H, horizontal teak
planking.
Having now particularly described and ascertained the nature and object of the
said Invention, and in what manner the same is to be performed or carried out in
practice, I hereby declare that I claim the Invention of Improved Arrangements

page_text: for Preventing or Nullifying the Destructive Action of Torpedoes and such like
Explosive Agents upon Ships or Vessels," substantially as the same is herein-before
set forth and described, and illustrated by the accompanying Drawings.
In witness whereof. I. the said Duncan Mac Iver Campbell, have hereunto set
my hand and seal, this Sixth day of February, in the year of our Lord One,
thousand eight hundred and seventy-eight.
AVitness,
NEI. MCTAVISH,
Overseer,
Loch Gair,
Argylshire.
DUNCAN MAC IVER CAMPBELL. (L..s.)