IMPROVEMENTS IN THE CONSTRUCTION OF IRON VESSELS AND IRON-PLATED SHIPS OF WAR
Year: 1861

page_text: PROVISIONAL SPECIFICATION left by Alfred Bevan at the Office of
the Commissioners of Patents, with his Petition, on the 23rd October
1861.
I, ALFRED BEVAN, of Gravesend, Architect, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF IRON VESSELS
AND IRON-PLATED SHIPS OF WAR," to be as follows:-
My Invention relates to a novel mode of constructing the frames of iron
vessels, more particularly vessels of war, and especially suited for war ships, the
sides of which are covered with armour plates superadded to the skin of the
vessel, or having sides or plating of such increased thickness as may be intended
to resist the penetration of projectiles; also to the mode of forming or con-
structing and applying armour plating or the metallic covering intended to
be applied to the sides of the hulls of ships of war as a protection against
projectiles.
That part or portion of my Invention which relates to the construction of
the frames of ships consists in the substitution for the ordinary single or double
angle irons and the rivetting together thereof for the purpose of forming the
frames or ribs and structural arrangements, by which the required form and
strength or power of resistance is given and the means provided for supporting
the outer skin or shell of a series of rolled bars of suitable sections combined
together, chiefly by means of dovetails, and framed or secured together in a
box-like form, placed at suitable intervals apart, they in turn forming, in
conjunction with the horizontal strengthening pieces, stringers, or their equi-
valents, a series of cellular divisions, by which the surface of the plating is

page_text: supported in the greatest number of parts, or the unsupported area reduced to
a minimum. In cases where the armour plating can be applied direct to the
framing of the ship, I attach or connect the plates thereto by means of dove-
tailed projections, from the back of each box-like vertical rib or frame, taking
into grooves formed in suitable ribs or projections rolled thereon. Instead of
the frames terminating with the line of the upper deck, I continue them to the
full height of the bulwarks surrounding the upper deck, and I frame the whole
together by means of a rolled bar or rail, forming a cap bar or bulwark rail,
having a projecting bead or nose piece along each edge, the under side or
under face of the bulwark rail being under-cut or dovetailed, so as to securely
frame the external plating or shell with the vertical box ribs or frame pieces.
In war ships the vertical plates forming the bulwarks, being of a sufficient
thickness to resist projectiles, may be pierced with loop holes or apertures for
permitting the discharge of small arms, the recesses formed by the vertical
box frames and the cap bar or bulwark rail forming a shot-proof mantlet
for each marksman. Instead of rolling armour plates plain and of uniform
thickness throughout, and attaching them by drilling holes therein, and
rivetting or bolting them to the sides of the ship in the ordinary manner, and
instead of providing vertical division bars or frame pieces, between a pair of
which bars each plate has to be slid, and instead of tapping holes into the
back of armour plates, and screwing thereunto plain or hooked bolts, or any
of the contrivances which have heretofore been proposed, I roll plates with
ribs at the back thereof in two or more places in the width thereof, as, for
instance, at each vertical edge and in the middle of the width thereof, or there
may be two of such ribs or projections. I form a dovetailed groove in each
of the outer projections, into which one of the two dovetails at the back of the
flat bar of each vertical box frame or rib is made to take into, whilst the other
of the projecting dovetails takes into the groove formed in the projecting rib
of the next vertical plate, and thus they are, as it were, clamped together; or
where the inner edge of the rib along the vertical edge of each plate is under-
cut or dovetailed, instead of having a dovetailed groove formed therein, the
plate or bar by which the plates are to be clamped together or secured may
be formed with its outer edge projecting and undercut so as to embrace the
whole length of the rib, or form one dovetail of the full width. In like manner
the rib or projection rolled in the middle of the plate (or there may be more
than one) is similarly formed, and the vertical box frame or rib is in like
manner connected with the plate. The vertical and horizontal edges of the
plates may be square and butt together in the ordinary manner, or they may
be planed of any suitable angular form for the better "bonding" or securing

page_text: the whole; but whatever the form of edge may be, the surfaces of the joining
plates are to be brought into contact. The spaces between the vertical box
framing or ribs, as described, may be divided by horizontal shelf pieces, with a
flat foot plate forming a covering plate or band for each horizontal joint of the
external or armour plating, and thus forming small divisions of square or
parallelogram form, which should extend from a suitable distance below the
water line to the upper deck, or throughout the space protected by the armour
plating, or having an extra thickness of plating thereon. Instead of continuous
bars for clamping together plates at their backs by means of the ribs thereon,
short dovetailed pieces or clips may be employed to secure them together; in
like manner, the vertical tapered or plain section bars may be secured together
by clip pieces. The combined horizontal shelf pieces and stringers may be
fastened to the vertical bars forming the frames by means of bolts and nuts,
or stud pieces screwed at each end, or double screwed bolts, or they may
be rivetted.