Improvements in Collapsible Boats.
Year: 1889

page_text: Date of Application, 15th Aug., 1889
Complete Specification Left, 15th May, 1890-Accepted, 28th June, 1890
PROVISIONAL SPECIFICATION.
Improvements in Collapsible Boats.
I, CHARLES HENDERSON, of 9 York Street, Glasgow, Lanarkshire, Engineer, do
hereby declare the nature of my invention to be as follows:-
This Invention comprises a new or improved construction and arrangement and
combination of the parts of collapsible boats which will collapse vertically to a hori-
zontal position to take up little height and be stowed over each other horizontally in
numbers under the present davits and putting out and lowering or launching
appliances on the decks of ships or vessels, without interfering with the proper
working of the vessel or taking up more deck space or increasing the top hamper or
gear.
The nature and novelty of my invention consist all as follows:-According to one
construction or arrangement of the parts of my improvements in collapsible boats, I
construct the bottom part of the boat, preferably of an ordinary shape beneath, formed
by the outer shell, with keel running from bow to stern and curved alike to the
opposite ends that either end may form the how or stern. I make this bottom as an.
air-tight hollow shallow case with an outer lower and upper shell, having the upper
shell preferably nearly flat to form the floor or bottom of the boat, and preferably
with transverse air-tight partitions and compartments between the shells to give
rigidity and floating power to the whole bottom and boat. Round the outer upper
edge of this lower cased bottom I secure a longitudinal stringer the desired shape of
the boat, and over this I mount and fit the gunwale much of the same shape, but wider
and longer, to be raised and lowered over the said stringer and bottom; and I cor.nect
to the under side of the gunwale by chains or links which will collapse, another
longitudinal stringer near the level of the thwarts and to which the ends of these
would be secured by brackets or otherwise, but I might have also longitudinal
stringers below this thwart stringer when desired. The bow and stern ends of each
stringer would be attached to each other, and have a check on their inside to admit
of the folding up of a bow and stern post, which would be jointed below to the bow
and stern of the floating case. A certain amount of sheer or rise fore-and-aft at the
gunwale may be obtained by varying the depth of the gunwale at this part; but
when considerable sheer is required, I binge or connect an auxiliary triangular
or V-gunwale fore-and-aft over the main horizontal gunwale, which will be hinged
to main gunwale towards the ends, and secured at apex to give desired height of
sheer at stem and stern posts to which it is secured by a simple locking device
when raised to its full height above the main gunwale frame. The sides of the
boat would be constructed of a single or double thickness of oiled or other
waterproof coated canvas, having its lower edge secured to the bottom floating
case or shell of the boat, or to the stringer over it, and also have its upper edge
secured to the outside of the gunwale and to the circumferential stringer under it
to which the ends of the thwarts are secured, preferably by screws and rounded
hardwood laths outside, which would form fenders and protect the outer canvas
skin from being cut or bruised; and in some cases a double shell or thickness. of
canvas might be used, secured in like manner to the inner side of the lower stringers
and to the gunwale above, so as to make separate circumferential airtight com-
partments between these thicknesses of canvas and the stringers and gunwale when
this inner thickness of canvas was used, and which compartments might have valves
for allowing the air into them as the sides of the boat were raised and escape from
them when being lowered. The thwarts and frames would be secured to brackets

page_text: bolted over the canvas to the stringers and gunwhale respectively, that is with the
canvas between the brackets and the stringers and gunwale. Angled flexible stays,
as ropes, might be used covered with wood ferrules or balls on each quarter of the
stem and stern ends to strengthen the outer canvas, so as to be raised and stretched
with the upper hinged part of the gunwale. This boat would also have a straight
keelson up the top centre of the floating bottom case, fitted with sliding plates each
sliding from the centre towards the bow and stern respectively to collapse the boat,
and towards each other in the centre to raise the boat as hereinafter described.
Each of these sliding plates would have one half of the frames of the boat jointed to
it in the centre by journal brackets, on which the frames would swivel in the centre,
while the upper ends of these frames would be jointed to the inner or under side of
the gunwale. The adjacent ends of each sliding plate would be so connected by
ropes to the upper part of the bow and stern posts, that when these were lifted by the
tackle of the davits to lift the whole boat, they would first raise the stern posts and
pull these ropes, so as to draw the sliding plates and lower parts of the frames secured
to them at the keelson, towards each other, and swivel the frames up vertically on
their joint connections to the plates and gunwale, at the same time raising the gun-
wale and stringers up from the floating cased bottom of the boat, and draw the bow
and stern posts tight into spring or other catches formed under the checks of the
gunwale, or the hinged raising and lowering part of the gunwale at the bow and
stern, and thus at the same time raise and secure the gunwale and the stringer con-
nected to it. One end of the wire or other ropes is attached to the upper apex end of
the hinged part of the gunwale at the bow and stern, so as to be raised by a pulley at
the upper part of the bow and stern posts, as these were raised by the tackle of the
davits, while these horizontal collapsing boats would all be collapsed horizontally on
the deck or floors under the davits. The mere folding in and lowering of the stem
and stern posts allows the frames and their slides to collapse horizontally with the
gunwale and stringers over the cased bottom of each boat. In some cases a fore and
aft central beam may be attached under the thwarts, and have the drawing wire ropes
so passed under this and guide pulleys leading to the top of the stem and stern posts
as to raise this and the thwarts while sliding and raising the frames as before
described. And stays might be so hinged under this upper longitudinal beam, or to
the thwarts as to be folded down and secured to the keelson below, or to the top of
the floating bottom of the boat. When desired, loose floor planks for walking on
might be mounted loose over the lower swivelling part of the frames, either resting on
these or resting on laths or supports laid between them on the upper shell of the
floating bottom of the boat. Although it is preferred to raise these boats from the
horizontal to the vertical position by the tackle of the davits, it will be understood
that they could be raised by any ordinary tackle, or by the men placed round the sides
of the gunwale.
The lower floating part of these collapsible boats would preferably be made of sheet
steel galvanized or otherwise protected, but they might be made of jointed planks of
wood, as many other pontoons and floating vessels are made; or otherwise they might
be made of open frame work transversely and longitudinally, and have the canvas
stretched right round under the outside of this floating bottom or frame, with longi-
tudinal protecting laths outside the canvas, and on the inside for the floor of this lower
floating frame, within which fixed or removable close air-tight vessels as cases or bags
might be fitted to give the buoyancy to this bottom floating frame. The stringers
and gunwale might either be made of hard wood or metal, or wood and metal com-
bined, and the frames would preferably be made of angle iron, or of flat iron filled in
with wood sides, or these might all be made of tubular steel or other metal for lightness
and strength.

page_text: COMPLETE SPECIFICATION.
Improvements in Collapsible Boats.
I, CHARLES HENDERSON of 9 York Street, Glasgow, Lanarkshire, Engineer, do
hereby declare the nature of my invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement in writing reference being had to the accompanying Sheet of Drawings,
and to the letters and figures marked thereon, that is to say :-
My Invention comprises a new or improved construction or arrangement and com-
bination of the parts of collapsible boats which will collapse vertically to a horizontal
position to take up little height and be stowed over each other horizontally in numbers
under the present davits and putting out and lowering or launching appliances on the
decks of ships or vessels, without interfering with the proper working of the vessel or
taking up more deck space or increasing the top hamper or gear.
And in order that my said invention and the manner of performing or carrying the
same into effect or practice may be properly understood, I have hereunto appended an
explanatory sheet of Drawings, in which the same reference letters are used to
indicate corresponding parts in all the figures where shown. Figure 1 is a longi-
tudinal sectional elevation of a collapsible boat in its raised position, taken near the
line 1-1 of Figure 2, as constructed in accordance with one arrangement of my
improvements. Figure 2 is a plan view corresponding to Figure 1, the one longi-
tudinal half of the boat being shown as when in its raised position, and the other half
in its folded down or collapsed position, with the thwarts C, removed to show the
transverse folding tubular frames or rails D, more clearly. Figure 3 is a transverse
sectional elevation taken near the centre of Figure 2, but to a larger scale, showing
the boat in its collapsed or folded down position; Figure 4 is a sectional elevation
broken away, of a transverse half of the boat in its folded up position. Figure 5 is a
side elevation of one of the oscillating stays C2 which carries the thwarts C showing
this to an enlarged scale detached. Figure 6 is a similar view showing the upper
part of one of the tubular frames D to a large scale. Figure 7 is a transverse
sectional elevation of the boat broken away, corresponding to Figure 4, but con-
structed with a double gunwale B B', and a single flat bottom F3. Figures 8 and 9
are elevations broken away of the stem and stern ends E of the boat, showing
alternative arrangements for attaching the hoisting chain and raising the boat from its
collapsed position.
Referring to Figures 1 to 6 of these Drawings:-According to this arrangement
of the parts of my improvements in collapsible boats, I construct the bottom part A A¹,
of the boat, preferably of an ordinary hollow shape beneath the floor A, formed by
the outer shell A¹, with keel A¹¹ inside and partly outside the lower part between
the floor A and outer shell A¹ running from bow to stern, and curved alike to the
opposite ends A² that either end may form the bow or stern. I make this bottom A A¹
as an air-tight hollow shallow case A" with an outer lower and upper shell, having
the upper shell A, preferably nearly flat to form the floor or bottom of the boat, and
preferably with longitudinal or transverse air-tight partitions and compartments All
between the shells to give rigidity and floating power to the whole bottom and boat.
Round the outer upper edge of this lower cased bottom A A¹, I secure a flat longi-
tudinal stringer A³ the desired shape of the boat, reaching from the bow to the
stern A2 A2, and over this I mount and fit the gunwale much of the same shape, but wider
and longer and preferably in two thicknesses of wood B, B1, to be raised and lowered
over the said stringer A³ and bottom. I connect some distance under the part B of
the gunwale another longitudinal stringer A preferably a seat stringer on each side
which stringer does not extend to the bow and stern A², and is cut and jointed in the
centre by a lower thickness at A³, preferably on the upper side and level of the
thwarts C which have their ends secured, by joint brackets and pins at C¹, or
otherwise, to the main oscillating frames D of the boat, (or this might be done by
chains or links which will collapse, or by rigid wood planking or metal sheets), but I

page_text: might have also longitudinal stringers below this thwart stringer A* when desired,
preferably outside the frames D and attached to the canvas a or between the two
layers of canvas when these are used. The bow and stern ends A2 of the stringers As
are attached to each other, and the bow and stern posts E are jointed below at E¹ by
flat iron joints to the floating case. A certain amount of shear or rise fore-and-aft of
the gunwale B B¹ may be obtained by varying the depth of the upper part B¹ of the
gunwale; but when considerable shear is required, I hinge or connect an auxiliary
triangular or V-part B" of the gunwale fore-and-aft over the main horizontal
gunwale B, which will be hinged to main gunwale towards the ends at B¹¹ and
secured at apex B² to give desired height of shear to the top E" of the stem and stern
posts E to which it is secured by a simple locking pin E or other device when
raised to its full height above the main gunwale frame B. The sides of the boat are
constructed of a single or double thickness of oiled or other waterproof coated canvas a
having its lower edge secured by a lath at a¹ to the bottom floating case or shell of
the boat, or to the stringer A³ over it, and also have its upper edge secured by another
lath at all to the outside of the gunwale B, and it might be to any circumferential
stringer under it, preferably by screws and rounded hardwood laths outside, which
would form fenders and protect the outer canvas skin from being cut or bruised; and
in some cases a double shell or thickness of canvas a might be used, secured in like
manner to the inner side of the lower stringers A3 and to the gunwale B B above, so
as to make separate circumferential air tight. compartments between these thicknesses
of canvas and the stringers and gunwale when this inner thickness of canvas was
used, and which compartments might have valves for allowing the air into them as
the sides of the boat were raised and escape from them when being lowered; and in
this case the thwarts C and frames D are secured to brackets bolted over the canvas a
to the stringers A³ and gunwale B B¹, respectively, that is having the canvas a
between the brackets and the stringers and gunwale. Angied flexible stays, as
ropes might be used covered with wood ferrules or balls on each quarter of the
stem and stern ends to strengthen the outer canvas a and so attached to the lower
part of the bow and stern A2 and to the under part of the gunwale B as to be raised
and stretched when the gunwale is raised. This boat has a straight wood and iron
keelson F secured up the top centre of the floating bottom case over the floor A and
keel A and is fitted with sliding plates F1 F1, each sliding from near the centre
towards the bow and stern respectively, or transversely, to collapse the frames D D¹
and boat, and towards each other in the centre to raise the frames D D¹ and boat as
hereinafter described. Each of these sliding plates F1 has one half of the frames D
of the boat jointed to it in the centre, and the other plate F" to the frames D¹ by
journal brackets at f on which the frames swivel in the centre in opposite directions,
while the upper ends of these frames are jointed at f¹ to the underside, or it
might be the inner side of the gunwale B. The adjacent ends F2 of each sliding
plate F1 F1 are so connected by wire or other ropes f¹ direct or through hooks 2 to
the upper part of the bow and stern posts E E, that when these are lifted by the chains e
and tackle of the davits hooked to these chains to lift the whole boat, they would first raise
the stem and stern posts E E, and pull these ropes f¹ so as to draw the sliding
plates F1 F and lower parts of the frames D D₁ secured to them at the keelson,
towards each other, and swivel the frames up vertically on their joint connections
at ff to the sliding plates and gunwale B B¹, at the same time raising the
gunwale B B and stringers A4 and thwarts C up from the floor A of the floating
cased bottom of the boat up to their highest position and draw the bow and stern
posts E out to their highest position and secure all by a pin E or it might be
spring or other catches through the checks of the gunwale B B and upper end E" of
the bow and stern posts E E. The pulling on the wire ropes fil in raising the stem
and stern posts E E, draws the near ends F2 of the sliding plates F1 F1 towards each
other in raising the frames D D¹ and draw hooks f on these ends over catches f³ to
hold the plates F1 F1 and frames D D¹ in their said raised position, until the
books are unlocked by hand. The thwarts C are held up in the centre by
oscillating stays C² jointed at their upper ends C¹¹ to the under side of each thwart,

page_text: and at their lower ends secured to near the centre of each stay on each side of the
keelson plate F where they have a projection at C₁ which takes under this plate and
retains the sliding plates F1 F1, in the centre over the keelson, as seen particularly
in the enlarged views Figures 5 and 6. The inner ends of the chains e which draw
up the boat are either attached to an eye F, or passed through it secured to the
centre of the keelson F of the boat, and the other free ends of these chains e are
secured to the ends of the raising gunwale B at e¹ and pass over antifriction
pulleys el on the upper end of the stem and stern posts E E, so as to be raised by
the tackle of the davits at the same time as these chains e raise the bow and stern
posts E E, while these horizontal collapsing boats would all be collapsed horizontally
on the deck or floors of the ships under the davits when these chains e were
slackened. The mere folding in and lowering of the stem and stern posts E E
allows the frames D D' and their slides F F to collapse horizontally and.
longitudinally with the continuous gunwales and stringers over the floor A and
bottom of the boat when the hooks f2 are disengaged. In some cases a fore and aft
central beam may be attached under the thwarts C, and have the drawing wire
ropes f¹¹, so passed under this and guide pulleys leading to the top of the stem and
stern posts E E as to raise this and the thwarts while sliding and raising the frames
as before described. And stays analogous to those C2 might be so hinged under this
upper longitudinal beam, or to the thwarts Cas to be folded down and secured to
the keelson below, or to the top of the floating bottom of the boat. When desired,
loose floor planks for walking on might be mounted over the lower swivelling part of
the frames D D' either resting on these or resting on laths or supports laid between
them on the upper floor A of the bottom of the boat analogous to the fixed floor
shown at 3 in Figure 7. Although it is preferred to raise these boats from the
horizontal to the vertical position by the tackle of the davits hooked to rings on the
ends of the chains e e, it will be understood that they could be raised by any
ordinary tackle, or by lines attached to the top of the stem and stern posts E
to be drawn up, or by the men placed round the sides of the gunwale.
The lower floating parts A¹ A¹ of these collapsible boats are preferably made of
sheet steel galvanized or otherwise protected, but they might be made of double
jointed planks of wood, as many other pontoons and floating vessels are made and as
shown in the Drawings; or otherwise they might be made of open frame work
transversely and longitudinally and have the canvas a stretched right round under
the outside of this floating bottom or frame, with longitudinal protecting laths
outside the canvas, and on the inside for the floor of this lower floating frame, within
which fixed or removable close air-tight vessels air cases or bags might be fitted to
give the buoyancy to this bottom floating frame. The stringers A³ A4 and
gunwale B B' might either be made of hard wood, or of metal, or of wood and metal
combined, and the oscillating frames D D¹, might be made of angle iron, or of flat
iron filled in with wood sides, or these might all be made of tubular steel or other
tubular metal for lightness and strength as the frames D D¹ are shown in the
drawings. In Figures 7, 8, and 9, the bottom A¹ of the boat is made in the form of
a flat bottom formed of double boards with a keel A111 outside and the inner
stringer A3 at the outer edge and with a strong stringer A³ outside, to the contour
of the bottom, between which and the inner floor stringer A³, the lower edge of the
canvas a is secured; while the upper edge is secured to the lower stringer B of the
gunwale of the boat, with a protecting lath all outside. And the canvas a is shown
as protected from rubbing on the outer edges of the floor A of the boat and of the
frames D by laths or light stringers at all on the inside and outside; while the
gunwale in this arrangement is shown as formed by a lower and upper strong
stringer B B. The whole gunwale down to the depth of the thwarts C is covered in
by wood boards at B3 on the outside and is connected by strong wood or iron plates
at B at bow and stern, outside the upper ends of bow and stern posts E E, while
the lower stringer B of the gunwale is jointed at f¹ to the upper ends of the frames D
and to the thwarts C by strong knees and plates C³, and as seen particularly in
Figures 8, and 9 hooks e² are shown as attached by straps E2 to the upper ends E"

page_text: of the bow and stern posts E E, for the hoisting tackle to be directly attached to in
this arrangement.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First. The construction, or arrangement and combination of the parts of boats,
in which the frames, gunwales, and seats collapse from a vertical to a horizontal
position by means of sliding or jointed frames or supports upon a rigid flat bottom
or frame, substantially as herein described in reference to and shown in the
accompanying Drawings.
Second. The constructing of collapsible boats with continuous single or double
rigid horizontal gunwales connected at their ends which collapse vertically to the
lower part of the boat, substantially as and in the manner herein described in
reference to and shown in the accompanying Drawings.
Third. The constructing of collapsible boats with a series of stringers running fore
and aft, and collapsing vertically with the gunwales, substantially as herein descirbed
in reference to and shown in the accompanying Drawings,
Fourth. The constructing of the frames, or the gunwales, and the stringers of
collapsible boats of steels or other metal tubes, substantially as herein described in
reference to and shown in the accompanying Drawings.
Fifth. The constructing of boats which collapse from a vertical to a horizontal
position with air-tight buoyant chambers in the flat bottom parts, and with air
chambers between the layers of canvas enclosing the stringers, substantially as herein
described, in reference to and shown in the accompanying Drawings.
Sixth. In a boat which collapses from a vertical to a horizontal position the con-
structing of the bottom of a hollow buoyant or water-tight flat form, or open frame
form, substantially as herein described in reference to and shown in the accompanying
Drawings.
Seventh. In a boat which collapses from a vertical to a horizontal position, on a
rigid flat bottom, the arrangement and use of binged stem and stern posts, so
connected by ropes to the swivelling frames or their slides, that when the posts are
raised by the lifting tackle the frames are simultaneously raised from the horizontal
to the vertical position with their gunwales and locked there in the boat form,
substantially as herein described in reference to and shown in the accompanying
Drawings..