CERTAIN IMPROVEMENTS IN PROPELLING SHIPS AND BOATS
Year: 1843

page_text: TO ALL TO HOM HESE PRESENTS
WALKER junior, of Glasgow, Merchant, send greeting.
UME, 1, ALBERT
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Eighteenth day of May, in the sixth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Robert
Walker junior, my exors, adiiors, and assigns, Her especial licence, full power,
sole privilege and authority, that I, the said Robert Walker junior, my exors,
adiiors, and assigns, and such others as I, the said Robert Walker junior, my
exors, admiors, 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
that part of Her said Majesty's United Kingdom of Great Britain and
Ireland called England, Her Dominion of Wales, and the Town of Berwick-
upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN PROPELLING SHIPS
AND BOATS;" in which said Letters Patent there is contained a proviso that I,
the said Robert Walker junior, shall cause a particular description of the
nature of my said Invention, and the manner in which the same is to be per-
formed, under my hand and seal, to be inrolled in Her Majesty's High Court
of Chancery within six calendar months next and immediately after the date
of the said in part recited Letters Patent, as in and by the same, reference
being thereunto had, will more fully and at large appear.
the said
NOW KNOW YE, that in compliance with the said proviso,
Robert Walker junior, do hereby declare that the nature of the said Inven-

page_text: tion, and in what manner the same is to be performed, are fully described and
ascertained in and by the following Specification thercof, reference being had
to the Drawings hereunto annexed, that is to say:-
The nature of my said Invention consists in propelling ships and boats by
means of a screw or shaft with radial arms, which screw or shaft is caused to
revolve in a horizontal or horizontally inclined cylinder or circular channel
placed inside of the vessel, and having two or more open passages communi-
cating with the water outside.
Figure 1 of the Drawings annexed represents a sectional elevation, and
Figure 2 a bottom view of the hull of a vessel constructed on the above plan.
A is the cylinder or circular channel in which the screw is made to revolve
by suitable machinery with which it is connected at F. The cylinder A com-
municates with the water outside on each side of the cutwater at C, and on
each side of the keel at B. The revolving of the screw causes the water to
enter at C, and be ejected at B, or vice versâ, thus propelling the vessel
forward or backward.
Figure 3 is an inside, and Figure 4 an outside view of a vessel having the
cylinder or circular channel placed near the centre of the vessel. The revo-
lution of the screw in the cylinder A causes the water to enter at C, C, and
be ejected at B, B, or vice versâ'; thus, as in the former case, propelling the
vessel forward or backward. The propelling power may be applied in this
case either before or behind the cylinder.
Figure 5 is an inside, and Figure 6 a bottom view of a vessel differing only
from Figures 1 and 2 in the mode of ejecting the water behind. In Figures 1
and 2 the water is forced out at an opening at the bottom of the vessel (divided
by the keel) in a direction towards the stern; but in 5 and 6 it flows through
two separate passages, one on each side of the vessel, in a direction towards
the stern. In Figures 1 and 2, and also in Figures 5 and 6, the screw and
cylinder (or circular channel), with its passages, may be placed in a reverse
position at the stern of the vessel, in which case the propelling power will be
placed before the cylinder, and the water will be taken in at B, in Figures 1
and 2, and B, B, in Figures 5 and 6, and in both cases forced out at C'when
the vessel is to be propelled forwards, or vice versa. Were valves placed at
the mouths of the various communications with the water outside, the working
of these valves might greatly facilitate the steering and turning of the vessel,
and in case of damage to the screw, they might be shut entirely until it was
repaired. In all the cases before described a screw, on the plan of what is
commonly called the screw of Archimedes, is employed; but instead of such
screw a horizontal shaft, with radial arins, may be employed, which 'arms" may