AN IMPROVED MODE OF PROPELLING SHIPS AND VESSELS AT SEA AND IN NAVIGABLE WATERS
Year: 1840

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
BLAXLAND, of Greenwich, in the County of Kent, Engineer, send greeting.
WHEREAS Her most Gracious Majesty Queen Victoria, by Her Letters
Patent under the Great. Seal of Great Britain, bearing date at Westminster,
the Twenty-eighth day of November, in the fourth year of Her reign, did give
and grant unto me, the said George Blaxland, my exors, admors, and assigns,
Her special license, full power, sole privilege and authority, that I, the said
George Blaxland, my exors, admors, and assigns, and every of them, by myself
and themselves, or by my or their deputy or deputies, servants or agents, or
such others as I, the said George Blaxland, my exors, admors, 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 law-
fully might make, use, exercise, and vend my Invention of "AN IMPROVED
MODE OF PROPELLING SHIPS AND VESSELS AT SEA AND IN NAVIGABLE WATERS,"
within that part of the United Kingdom of Great Britain and Ireland called
England, the Dominion of Wales, and Town of Berwick-upon-Tweed, and also
in all Her said Majesty's Colonies and Plantations abroad, in such manner as to
me, the said George Blaxland, my.exors, admors, and assigns, or any of them,
should in my or their discretions seem meet; and that I, the said George Blax-
land, my exors, admors, and assigns, should and lawfully might have and enjoy
the whole profit, benefit, commodity, and advantage from time to time coming,

page_text: growing, accruing, and arising, by reason of my said Invention, for and during
the term of years therein mentioned; in which Letters Patent there is con-
tained a proviso, that I, the said George Blaxland, should cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, by an instrument in writing under my hand and seal,
to be enrolled in Her said Majesty's High Court of Chancery within two
calendar months next and immediately after the date of tho said in part recited.
Letters Patent, reference being thereunto had, may more fully and at largo
appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
George Blaxland, do hereby declare and describe the nature of my said Inven-
tion, and the manner in which the same is to be performed, as follows:-
One or more inclined. planes or propellers are to be affixed at right angles
to a revolving horizontal shaft, placed over the after part of the keel forwards
of the rudder post, which inclined planes work in the water below the water
line in an opening formed in the dead wood of the vessel, but without any
bearing or journal beyond the inclined plane or planes, so as not in any way
to be attached to the rudder post. The planes being placed at right lines
enables them to pass through the water with the least possible friction. In
order to determine the angles at which the inclined plane or planes is or are
to be fixed to the revolving horizontal shaft, I draw a straight line, the length
of the circumference, as shown in the Diagram, Figure 1, from 1 to m, 56'54
inches; then I set out the angle at which I intend to set the first or outermost
inclined plane, and raise a perpendicular from the length of the circumference,
and at that point where it intersects the angular line which is determined
upon will be the distance passed through at one revolution; then I draw a line
parallel to the base line, and in like manner set off the other different distances,
as from to n, 50'26 inches the circumference; I there find that an angle of
33 degrees is necessary to give the same distance advanced, and in like
manner I proceed to set out for the different circumferences or diameters
required. I prefer, however, not carrying it fürther to the centre than where
an angle of 45 degrees would be required to give the distance. I rivet the
inclined planes, which I prefer divided into three or more parts, cach part
being separately rivetted on to an arm, as shewn in Figure 8. The speed of
the revolving horizontal shaft upon which the inclined planes are fixed is to
be got up in manner following:-I place an intermediate friction wheel or
friction wheels between the larger driving drum and the smaller driven drum,
as shewn at Figures 6 and 8 in the Drawings, which friction wheel or wheels
revolve with the driving drum, and is again borne and communicates its motion

page_text: to the driven drum. I bring the friction wheel or wheels into or out of the
line of centres by means of a screw, as shewn at Figures 6, whereby the strap
or band e, which passes over the said driving and driven drums, may be
tightened or slackened, as occasion may require. In order to keep the drums
parallel to each other when the shafts are out of a parallel line, I leave a
spherical boss upon the shaft, and make the drum in two parts, so as that the
boss of the two parts of the drum may fit the boss on the shaft, and put them
together by means of screws, so as to form an universal joint, and a clutch or
driving coupling is keyed on to the shaft to carry the drum round, as shewn at
Figure 7. The strap or band may be made to pass upon the surface of the
intermediate wheel or wheels, as shewn at Figure 10. Where it may be required
for the propeller shaft to rise and fall with the tightening and slackening of
the strap a bearing is used, as shewn at Figure 9. I grind the part h into
the socket i, so as to make it water-tight, but at the same time to move freely
in and out of its socket, and the part h may be kept up, to the spherical part
of the shaft by means of a spring or springs; but I do not consider it indis-
pensably necessary that the propeller shaft should rise and fall, having in my
experiments allowed the upper shaft (a) only to rise and fall with the tighten-
ing or slackening of the strap.. Figure 1 in the Drawing is the Diagrain
before described for finding the different angles of the inclined planes.
Figure 2 is a section or side view of the after part of a vessel, shewing the
application of the Invention as used on board the experimental boat Jane. a is
the main driving shaft from the engine; b, the driving drum; c, the inter-
inediate friction wheel; d, the driven drum; e, the strap; f. a pipe, carried
to any convenient part of the vessel, through which a mixture of oil and
tallow is applied to the gland or bearing where the revolving shaft passes
through the vessel; the mixture being put into a cylinder, in which a
piston is fitted and loaded with a weight, so as to force it into the gland or
bearing. The propeller is here shewn with an undivided inclined plane.
Figure 3, an end view of a propeller, with four series of inclined planes, each
divided into three parts. Figure 4 is an end view of the propeller on Figure 2.
Figure 5 is a section through y, y, of Figure 2, shewing three series of divided
planes, each divided into three parts. Figure 6 is a section through 2, %, of
Figure 2, shewing the mode of tightening the strap by means of the friction
wheel and screw, as applied on board the Jane. The letters in this Figure cor-
respond with those in Figure 2. Figure 7 shews a mode of keeping the drums
parallel to each other when the shafts are out of a parallel line with an inter-
mediate friction wheel; and Figure 8, the same, with two intermediate friction
wheels. Figure 9 shews the mode used for a bearing, where the propeller

page_text: shaft passes through the vessel, when it is required that the same may rise and
fall. Figure 10 shews the strap or band made to pass upon the surface of
one intermediate wheel.
In witness whereof, I, the said George Blaxland, have hereunto, set my
hand and seal, the Twenty-eighth day of January, in the year of our !
Lord One thousand eight hundred and forty-one.