IMPROVEMENTS IN SHELLS AND IN FUSES USED WITH SHELLS
Year: 1866

page_text: LETTERS PATENT to Charles Ambrose M°Evoy, of 28, Bedford Square,
in the County of Middlesex, for the Invention of "IMPROVEMENTS IN
SHELLS AND IN FUSES USED WITH SHELLS."
Sealed the 4th December 1866, and dated the 5th June 1866.
PROVISIONAL SPECIFICATION left by the said Charles Ambrose M°Evoy
at the Office of the Commissioners of Patents, with his Petition, on
the 5th June 1866.
I, CHARLES AMBROSE MCEVOY, of 28, Bedford Square, in the County of
Middlesex, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN SHELLS AND IN FUSES USED WITH SHELLS," to be as follows:-
This Invention has for its object improvements in shells and in fuses used
with shells. In constructing shells, whether the external case be cylindrical
or of a spherical or of other form, there is constructed in the interior of such
case an angular and by preference a rectangular chamber into which the
passage which receives the plug or bushing opens or communicates. This
chamber is to receive the charge of powder, but it also receives four or other
number of small shells, one in each angle of the chamber, such small shells
are passed through the passage which receives the bushing or plug. Each of

page_text: the small shells has its own time fuse which is ignited when the charge in the
principal shell is exploded. The charge of powder for bursting the principal
or large shell is contained in and occupies the space of the angular chamber
not occupied by the small shells. The plug or bushing of the large or outer
shell retains the small shells in their positions in the angles of the chambers.
In constructing impact shells a plug or bushing usually of brass is employed
which is hollow at its inner end, and has screwed into it a small chamber
which is open at one end, whilst at the other end there is a perforation in the
centre; between the open end of this chamber and the hollow compartment of
the plug or bushing is introduced a disc of metal which is perforated in the
centre. On one side of this disc there is a sphere or other form of hard
metal, which is connected by a thin wire to a metal tube which is on the
other side of the disc, and these parts are held together till the shell is
discharged from a gun or mortar, when they separate by the giving way of
the wire by the shock consequent on the discharge of the gun or mortar.
The tube contains powder, the time of burning of which determines the time
when the charge in the shell shall be ignited. The hollow chamber in the plug
or bushing is washed or coated with fulminate, so that on the sphere being
released it will on striking against part of the surface explode the fulminate
by which the powder in the tube will be ignited.
In constructing a time fuse for a shell the bush (usually of brass) is
formed conical except at the part where the screw thread is formed which is
to screw into the shell. The outer end of the bush or plug when the fuse
is not therein is closed by a screw cap or cover. The other or inner end of
the plug or bush is closed, and a slot is formed from end to end of that part
of the bush or plug which comes within the shell. The interior of the bush
or plug is conical to receive a conical tube containing the burning powder or
other material constituting the fuse. The conical tube of the fuse fits the
interior of the plug or bushing correctly. Around the fuse tube in a spiral
lino are perforations at graduated distances apart, and around the larger outer
end of the conical tube there is a graduated scale corresponding with the
perforations formed through the tube. At the outer end of the plug or
bushing there is a mark or arrow indicating the position of the slot before
mentioned, hence by placing the tube in the bush or plug in such manner
that one of the graduations comes opposite the arrow or pointer on the plug
or bushing, the perforation in the tube of the fuse corresponding with
graduations as before mentioned will come opposite the slot, and the fuse
will continue to burn till it arrives at that hole, and then the fire will pass
out through the slot to the charge in the shell. The ignition of a fuse of

page_text: a shell is obtained by means of a short tube, by preference of lead or tin,
containing fulminate, through which there is a rough wire which at its end
is suspended or attached to a cross wire in such manner than when the shell
is projected from a gun or mortar the wire will be drawn through the tub
containing the fulminate and thereby explode the same.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Ambrose M°Evoy in the Great Seal Patent Office
on the 5th December 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
AMBROSE McEvoy, of 28, Bedford Square, in the County of Middlesex, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of June, in the year of our Lord One
thousand eight hundred and sixty-six, in the twenty-ninth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Charles Ambrose M.Evoy, Her special licence that I, the said Charles
Ambrose M'Evoy, my executors, administrators, and assigns, or such others
as I, the said Charles Ambrose M°Evoy, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "IMPROVEMENTS IN SHELLS AND IN FUSES USED WITH SHELLS," upon the
condition (amongst others) that I, the said Charles Ambrose M°Evoy,
my executors or administrators, by an instrument in writing under my,'
or their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
NOW KNOW YE, that I, the said Charles Ambrose M°Evoy, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
This Invention has for its object improvements in shells, and in fuses used
with shells. In constructing shells, whether the external case be cylindrical or

page_text: of a spherical or of other form, there is constructed in the interior of such
case an angular, and by preference a rectangular chamber, into which the
passage which receives the plug or bushing opens or communicates. This
chamber is to receive the charge of powder, but it also receives four or
other number of small shells, one in each angle of the chamber, such small
shells are passed through the passage which receives the bushing or plug.
Each of the small shells has its own time fuse which is ignited when the
charge in the principal shell is exploded. The charge of powder for bursting
the principal or large shell is contained in and occupies the space of the
angular chamber not occupied by the small shells. The plug or bushing of
the large or outer shell retains the small shells in their positions in the angles
of the chambers.
Figure 1 is a transverse section of a spherical shell constructed in this
manner. a, a, is the outer shell or case of cast iron with a cubical cavity
within it, into which four cylindrical shells b, b, are introduced through the
opening which afterwards receives the screw plug or bushing c. A plan of
the shell with the secondary shells within it is shown at Figure 2; as will be
seen they are arranged in the angles of the cavity, where they become firmly
secured, when the plug or bushing c is screwed down upon them. In Figure
2 this plug or bushing has, not yet been inserted which allows of the tin
case d-containing the main bursting charge to be clearly seen, the plug or
bushing when in its place forms the top or cover of this case entering at a short
distance. In the centre of the plug or bushing is a hole to receive the fuse,
which may be of any convenient form, and the fuse hole is closed by a suitable
stopper until the shell is required for service, when the fuse is adjusted.
Figures 3 show in section one of the secondary shells 6 with its plug or fuse
6', the passage through the plug or fuse b' is filled with fuse composition and
is made of a length to burn the time desired.
Figure 4 is a plan of the plug or fuse b
1
Cylindrical and other shells may also according to my Invention be similarly
formed with cavities within them, into which secondary shells are fitted and
secured in position by screwing on the plug or bushing as above described.
Or in such cases the secondary shells may be secured in position by plug or
bottom screwed in or otherwise secured to the base of the shell. These shells
are intended principally for use against troops, and for this purpose they are s
very effective as each shell, arranged as is shown in the Drawing, gives five
distinct explosions.
In constructing impact fuses a plug or bushing, usually of brass, is employed
which is hollow at its inner end, and has screwed into it a small chamber

page_text: which is open at one end, whilst at the other end there is a perforation in the
centre. Between the open end of this chamber and the hollow compartment
of the plug or bushing is introduced a disc of metal whic is perforated in
the centre. On one side of this disc there is a sphere or other form of hard
metal which is connected by a thin wire to a metal tube which is on the other
side of the disc, and these parts are held together till the shell is discharged
from a gun or mortar when they separate by the giving way of the wire by
the shock consequent on the discharge of the gun or mortar. The tube
contains powder, the time of burning of which determines the time when the
charge in the shell shall be ignited. The hollow chamber in the plug or
bushing, or it may be the metal sphere, is washed or coated with fulminate,
so that the sphere being released it will on striking against part of the
surface explode the fulminate by which the powder in the tube will be
ignited.
Figure 5 is a longitudinal section of a fuse thus constructed. a, a, is a plug
or bushing screwed into a thread cut in the case of the shell, it has a cavity
on its under side into the mouth of which the piece 6 is screwed, and between
it and the part a a disc c is introduced, in the centre of which is a small
hole; d is a metal sphere which by a wire is connected with the tube e filled
with fuse composition. The wire connecting the sphere d with the tube s
passes through the hole in the disc c, as is shewn; the tube e fits the cylindrical
chamber in the piece b but is able to slide therein. When a shell with a
fuse such as described is fired from a gun or mortar the shock on firing
breaks the wire connecting the sphere d, and the tube e, and sets the sphere
free, then when the shell grazes on the ground or on water the sphere is
thrown violently against the sides of the cavity in the plug or bushing a, and
thereby explodes the fulminating priming; this priming may be applied to the
interior of the cavity, but I prefer to apply it to the surface of the sphere d
and to render it somewhat less sensitive by afterwards wrapping the sphere in
tin foil. When the fulminate explodes it ignites the composition in the tube,
which burns a time dependent on its nature and its length, and it then fires
the charge which should be immediately beneath. In this arrangement the
ignition takes place with equal certainty whatever be the position of the shell
at the time of grazing. This fuse is applicable for shells which it is desired
to discharge at a short interval after the graze, as for example, Shrapnel
shell. When it is desired that the shell should explode immediately on
impact I slightly modify the arrangement, as is shewn at Figure 6; in this case
the tube is substituted by a leaden weight with a stem passing through the
sphere and rivetted beyond, this stem is severed when the gun is fired, and when

page_text: the shell strikes, the fire resulting from the ignition of the fulminate passes
by the vent passages 61, 6', in the piece b to the charge. It is not essential
that the piece b should be so formed as to catch the leaden weight when it
becomes detached from the sphere as this weight may without inconvenienco
be allowed to pass back into the cavity of the shell. In each case it will be
´observed that the sphere (or striker) is set free without being displaced by the
fracture of the stem or instrument which restrained it, by the shock of the
explosion on firing the gun.
In constructing a time fuse for a shell the bushing (usually of brass) is
formed conical except at the part where the screw thread is formed which is
to screw into the shell. The outer end of the bushing or plug when the fuse
is not therein is closed by a screw cap or cover, the other or inner end of the
plug or bush is closed and a slot is formed from end to end of that part of
the bushing or plug which comes within the shell. The interior of the
bushing or plug is conical to receive a conical tube containing the burning
powder or other material constituting the fuze. The conical tube of the fuze
fits the interior of the plug or bushing correctly. Around the fuse tube in a
spiral line are perforations at graduated distances apart, and around the larger
outer end of the conical tube there is a graduated scale corresponding with
the perforations formed through the tube. At the outer end of the plug or
bushing there is a mark or arrow indicating the position of the slot before
mentioned, hence by placing the tube in the bushing or plug in such manner
that one of the graduations comes opposite the arrow or pointer on the plug
or bushing, the perforation in the tube of the fuse corresponding with the
graduation as before mentioned will come opposite the slot and the fuse will
continue to burn till it arrives at that hole, and then the fire will pass out
through the slot to the charge in the shell. The ignition of a fuse is obtained
by means of a short tube by preference of lead or tin containing fulminate,
through which there is a rough wire which at its end is suspended or attached
to a cross wire in such manner that when the shell is projected from a gun or
mortar the wire will be drawn through the tube containing the fulminate, and
thereby explode the same.
Figure 7 is a longitudinal section of the plug or bushing to receive the
fuse; Figure 8, a plan of the same; Figure 9, a side view; and Figure 10,
longitudinal section of the fuse.
The plug or bushing which is screwed into the shell has a taper hole within
it corresponding with the exterior form of the fuse, and entering this taper
hole is the long narrow slot a. The fuse case may be of paper or wood, it is
filled for a considerable portion of its length with fuse composition b, and

page_text: holes c, c, are bored in a spiral line passing once around it and opening
passages passing from the fuse composition 6 to the exterior of the fuse; d, d,'
are graduations around the head of the fuse representing seconds of time and
fractions thereof. When the fuse is required for use it is introduced into the
plug or bushing in such manner that one of the graduations corresponds with
the arrow on the top indicating the position of the slot a therein; then, as
will be seen when the composition has burnt a time corresponding with the
graduation selected, the fire will have arrived at the hole c opposite the slot
and will pass through and ignite the charge. If the gun or mortar used
allows a good deal of windage around the shell the flash on firing the piece
will be sufficient to ignite the composition in the fuse; but to insure this in
other cases I employ the leaden tube e, the interior of which is lined with
fulminating composition, and the roughened wire f is then passed through it
and the tube is by pressure nipped in upon the wire. The igniter thus formed
is suspended to a cross wire g fixed in the mouth of the fuse, and the shock
on firing the gun will be sufficient to draw the tube off the roughened wire
and so to fire the fulminate by the friction, the flash thus produced ignites
the composition 6.
Ignitors constructed according to my Invention are applicable to fuses of
other constructions.
In witness whereof, I, the said Charles Ambrose M°Evoy, have
hereunto set my hand and seal, this Fifth day of December, in
the year of our Lord One thousand eight hundred and sixty-six.
MCEVO