IMPROVED MEANS OF RESISTING CANNON SHOT, APPLICABLE TO FORTS, SHIPS, AND OTHER PLACES
Year: 1876

page_text: LETTERS PATENT to John Cox, of Bideford, in the County of Devon, for the
Invention of "IMPROVED MEANS OF RESISTING CANNON SHOT, APPLICABLE TO
FORTS, SHIPS, AND OTHER PLACES."
aled the 23rd March 1877, and dated the 29th September 18
PROVISIONAL SPECIFICATION left by the said John Cox at the Office of the
Commissioners of Patents on the 29th September 1876.
JOHN Cox, of Bideford, in the County of Devon. "IMPROVED MEANS OF RESISTING
CANNON SHOT, APPLICABLE TO FORTS, SHIPS, AND OTHER PLACES."
My Invention refers to the employment of metal chambers or cases which are
firmly secured to the sides of the place to be protected. The said chambers are
filled with compressed air, so that when a chamber is struck by a shot the com-
pressed air in the interior thereof causes the chamber to afford or become an elastic
cushion or bed, or the said chamber may be constructed so as to burst upon being
struck, and thus very materially aid in resisting the percussive force of the
projectiles.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Cox in the Great Seal Patent Office on the 29th March
1877.
JOHN Cox, of Bideford, in the County of Devon. "IMPROVED MEANS OF RESISTING
CANNON SHOT, APPLICABLE TO FORTS, SHIPS, AND OTHER PLACES."
My Invention refers to the employment of metal chambers or cases which are
firmly secured to the sides of the place to be protected. The said chambers are
filled with compressed air, so that when a chamber is struck by a shot the com-
pressed air in the interior thereof causes the chamber to afford or become an elastic
cushion or bed, or the said chamber may be constructed so as to burst upon being
struck, and thus very materially aid in resisting the percussive force of the
projectiles.
Figure 1 of the accompanying Drawings is a longitudinal section of one arrange-
ment, and Figure 2 a transverse section of same; a, a, represents the timber backing,
D 4.17

page_text: iron plating, or other surface or wall to which the chambers or cases are to be
attached for sole or further protection against shot or shell or other projectile;
b, b, are the chambers or cells which are fixed to the backing a by dovetail
feathers c, c, or in any other suitable manner, according to the nature of the backing a
The cell or chamber b is filled with compressed air and contains an interior circular
cell & containing air still more compressed; for instance, if b be charged with air
of 500 pounds pressure d may be charged with air of double that pressure. The
chambers or sets of chambers are united one to another by preference by means of
dovetail pieces c, or in any other suitable manner.
Figure 3 shews an end view of a cell fitted with diagonal dovetails, such as
might be used in case of having to replace a new cell for one that may have been
damaged.
Figure 4 shows a modified arrangement where the chamber b is fitted with one
or more perforated partitions d, as shewn. The chambers are in this case also filled
with compressed air. The object of the perforated partition is that in the event of
the cell being struck by a projectile the air contained in the outer compartment may
rush into the next compartment, causing a greater air pressure therein, and thus also
an increased resistance.
The air is supplied to the chambers by means of a pump provided for the purpose,
and the chambers are each fitted with a self-closing stop back valve.
I am aware that cells charged with compressed fluid has been proposed as a
backing for armour plates, and I therefore do not claim this.
I do not confine myself to the precise arrangements here set forth, so long as the
essential features of the Invention are retained, which are the employment of
chambers or cells b and d charged with compressed air as armour for the protection
of forts, ships, and other structures, substantially as set forth.
In witness whereof, I, the said John Cox, have hereunto set my hand and
seal, this Twenty-seventh day of March, in the year of our Lord One
thousand eight hundred and seventy-seven.