AN IMPROVEMENT OR IMPROVEMENTS IN THE MODE 02 MEANS OF PROPELLING VESSELS THROUGH WATER, AND PART OF WHICH MEANS MAY BE APPLIED TO OTHER USEFUL PURPOSES
Year: 1837

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
SPURGIN, of Guilford Street, Russell Square, in the County of Middlesex,
Doctor of Medicine, send greeting.
WHEREAS His late Majesty King William the Fourth, by His Letters
Patent under the Great Seal of the United Kingdom of Great Britain and
Ireland, bearing date at Westminster, the Eighth day of May now last past,
did give and grant unto me, the said John Spurgin, His especial licence, full
power, sole privilege and authority, that I, the said John Spurgin, my excecutors,
administrators, and assigns, or such others as I, the said John Spurgin, my
executors, administrators, or assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term of years
therein expressed, should and lawfully might make, use, exercise, and vend,
within England, Wales, and the Town of Berwick-upon-Tweed, my Invention
of "AN IMPROVEMENT OR IMPROVEMENTS IN THE MODE 02 MEANS OF PROPELLING
VESSELS THROUGH WATER, AND PART OF WHICH MEANS MAY BE APPLIED TO OTHER
USEFUL PURPOSES;" in which said Letters Patent there is contained a proviso
obliging me, the said John Spurgin, by an instrument in writing under my
hand and scal, particularly to describe and ascertain the nature of iny said
Invention, and in what manner the same is to be performed, and to cause the
same to be inrolled in His said Majesty's High Court of Chancery within six

page_text: calendar months next and immediately after the date of the said recited
Letters Patent, as in and by the same, reference being thereunto had, will
more fully appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Spurgin, do hereby declare that my said Invention, and the manner
in which the same is to be carried into effect, are shewn and explained
in the following description thereof, elucidated by the Drawings hereunto
annexed, as indicated by the figures and letters of reference herein contained,
that is to say-
My Invention, as it respects the means of propelling vessels through water,
consists in modifications of that class of paddles which are affixed to endless
chains, extended by and revolving on wheels or riggers, by which modifica-
tions the paddles may be regulated to enter the water, and to come out of it, at
any angle required for producing the best effect in propelling the vessel. It is
well known that sets of paddles have been heretofore affixed to endless chains,
carried around and extended horizontally by wheels or riggers turned by a
steam engine, sometimes with so much tension as to keep that part of the
chains between the riggers nearly straight, whereby the path of the paddles in
the water was nearly in a straight line; and sometimes the riggers were
situated.so near together in respect of the length of the chains, as to allow of
considerable swagging in the chains at the lower part, and thereby of carrying
the paddles through the water in a curve approximating to the arc of a circle
described by the revolution of a large paddle wheel. The evils of the tight
chains were found to be, that the riggers being usually and almost necessarily
of small diameters, the paddles to be sufficiently immersed must enter and
leave the water too obliquely for smooth and useful action; and when in the
water, the paddles, after the first impulsion, were acting only against water
already set in motion by that impulsion, and therefore the paddles could not
in their progress derive a continued beneficial force from the resistance of the
water. The evils experienced in the case of the swagging chains were, firstly,
that the paddles were not held firmly by the chains in a position at right angles
to their path, but were liable to be turned around upon their attachments to
the chains, and thus to yield to the water instead of deriving the requisite force
from its resistance; and, secondly, that being so loose, the chains with their
paddles were liable to be tossed about and deranged by the waves in rough
weather. The object of my Invention is to retain all the benefits, and avoid
all the evils of those two general modes; and I effect this object by making a
tightly extended pair of chains pass around two pair of riggers of compara-
tively small diameters, and over and under a pair of driving wheels of larger

page_text: diameters than the riggers, the pair of wheels being situated between the two
pairs of riggers, and being turned by the steam engine, and furnished with
teeth, which act against the cross bolts or rivets of the links of the chains, and
give them their motion. By this arrangement I am enabled to place the,
wheels higher or lower in respect to the extending riggers, or to vary their
proportionate diameters so as to obtain a determinate degree of descent of the
paddles into the water, and thus can command any angle of entering in and
coming out of the water, which may be requisite for efficient action, making
the path of the paddles in the water approximate to the arc of a circle
described by the circumference of a large paddle wheel of any given radius.
And I obtain a degree of firmness in the paddles by constructing the links of
the chains of considerable length, and by forming a flanch, on the back of each
middle link projecting over one side and both ends, the projections overlapping
part of the adjoining outer links at the working position, as herein-after shewn
and described. For small vessels, instead of a pair of chains, wheels, and
riggers, a set of paddles may be affixed to a single endless flat and broad chain,
and for very large vessels three or more chains may be employed.
endless chain, passing around a pair of extending riggers, and over and under
a driving wheel furnished with teeth, acting against the bolts or rivets of the
chain; Fig. 2, a plan of the same. The letters of reference indicate the same
parts in both the Figures. a, the side of the vessel; b, a frame bolted to the
side of the vessel; c, two bolts or studs passing through holes in the side of the
vessel, and through holes in the frame, in all which holes they fit tightly,
holding the frame firmly to the side of the vessel by means of four nuts d;
e, two bolts or studs, also passing through the side of the vessel and through
the frame, assisting to hold them more firmly together by means of the four
nuts f, but when these nuts are loosened the studs may be slidden in slots g,
formed in the frame and in the side of the vessel; h, four riggers, revolving
between collars upon the two studs e; k, part of the main shaft, proceeding
from and turned by the steam engine; 1, a pair of wheels fixed on and driven
by the main shaft; these wheels may have side flanches like the riggers, to
guide the chains, or the teeth may be made narrower at the tips than at the
roots, in order to perform the part of guides to the chains, when the flanches
are omitted; m, teeth formed around the wheels 1; n, a pair of endless chains,
each chain passing around and.tightly extended by two riggers, and embracing

page_text: the wheels
above and below, the links of the chain from centre to centre
of the rivets being made of the same length as the distance from middle to
middle of the teeth of the wheel; p, eight pair of forked studs in each chain,
the forked stud being formed in one piece with the link from which it pro-
jects; eight paddles, each held between the prongs of two forks, one fork
belonging to each chain; these paddles may be more or less in number, and, in
the case of small vessels, may be made of hard wood, strengthened crosswise
by straps of iron, as represented at '; or, as in the case of large vessels, they
may be made of iron plate; r, two cross leads, secured to the frame b and
through the side of the vessel, the cross heads being held by the four nuts s,
these cross heads forming also additional studs to give stability to the frame b;
t, two screws, working in the cross heads r, and pressing against the bolts or
studs e, by the medium of the blocks u, for the purpose of sliding the studs in the
slots g, and thereby of extending the chains n to the requisite degree of tension,
It will be necessary to produce this tension by an equal distance of sliding at
each end, in order that the teeth m of the wheel 7 may act smoothly against
the rivets of the chains n, both at the bottom and at the top of the wheel.
Diagonal braces and other supports must be added to the frame b, in such
forms and positions as the construction and magnitude of the vessel may require.
I have not shewn any, because they constitute no part of my Invention.
Fig. 3 represents a profile of part of a chain on an enlarged scale, shew-
ing an extension of the back piece in breadth, so as to bear on both the side
links, and an extension in length to meet and abut against the back piece of
the next middle link; Fig. 4, plan of the same; Fig. 5, profile of a link of the
middle tier, with a back piece or flanch projecting from both sides and both
ends for overlapping the next inner and outer links, reaching to the middle
of the length of those links, where it meets with and abuts against a similar
back piece or flanch belonging to the next middle link; Fig. 6, end view of the
The letters of reference signify the same parts in all the Figures.
v, the middle links; w, the back pieces, united with and forming part of the
middle links; a, the side links; y, the bolts and washers, cach bolt rivetted
through one middle and two side links.
same.
And I do further declare, that the part of my Invention which may be
applied to other useful purposes is the chain, herein-before described, particu-
larly that form shewn at Figures 3, 4, 5, and 6, being a chain capable of
supporting itself in nearly a horizontal position for a considerable length, and
which, therefore, may be called a self-supporting chain; and the purposes to
which such a chain may be applied are to the formation of a temporary bridge,
to be thrown from a ship to the shore in many situations, to form a platform

page_text: for passengers to go on shore or on board, which bridge may consist of two
chains laid parallel to each other, upon and across which chains a flooring of
wood may be secured. Such a self-supporting chain, being made of several
links in breadth; will form a flat chain, applicable for passing a considerable
distance horizontally, or inclined to the horizon, from a steam engine to a
rigger over a coal pit or other shaft; this chain requiring only a few inter-
mediate supporting pullies. Such a self-supporting chain, also formed into an
endless chain, and suspended from a rigger at the top of a pit or shaft, and
passing under another rigger near the bottom of the shaft, would, by reason of
its stiffness, admit of platforms projecting horizontally being attached in the
manner of the paddles of my propelling apparatus, herein-before described,
upon which platform persons may stand to ascend and descend by the con-
tinual revolution of this endless chain, turned by a steam engine or other
power. Or goods may be laid on such platforms, and raised or lowered from
floor to floor in a warehouse, where the descending goods would oftentimes so
nearly balance the ascending goods as to require but little power to set the
chain in motion. In this case, for the sake of simplifying the description, one
chain only has been mentioned, but I prefer two chains with bars between
them like the rings of a ladder, and which may indeed form a ladder, from
platform to platform; and the platforms may be made with two hooks to hang
on upon the rungs.
I have purposely omitted, as useless, the giving of precise dimensions of any
of the parts of my Invention; because, as is obvious, the dimensions will have
to be varied to suit the peculiar circumstances under which the apparatus may
be employed; as, for instance, in large vessels all the parts will have to be made
many times the magnitude of those of small vessels, and in ships platforms or
temporary bridges the strength of the links must increase with the length of
the bridge.
And I do further declare, that I lay no claim to the attaching of paddles to
or the carrying of them around by endless chains extended by riggers. But I
do claim the attaching of paddles to an endless chain passing around and
extended by two riggers, and at the same time passing over and under, and
being driven by a toothed wheel situated between the riggers, for the purpose
of propelling vessels through water, as herein-before particularly shewn and
described. And I claim the construction of self-supporting chains, as herein-
before described. And I claim the use of one, two, or more of such chains for
carrying one set of paddles. And I claim the application of this self-supporting
chain to the formation of ships' landing platforms, to the construction of flat
pit chains, and to such other purposes as may require a chain capable of sup-

page_text: porting itself in a horizontal or an inclined position for a considerable distance,
and yet have flexibility in the other direction for passing around a rigger or
pulley, as herein-before particularly shewn and explained.
In witness whereof, I, the said John Spurgin, have hereunto set my
hand and seal, this Seventh day of November, in the year of our Lord
One thousand eight hundred and thirty-seven.