Year: 1842

page_text: LONDON:
PRINTED BY GEORGE E. EYRE AND WILLIAM SPOTTISWOODE,
PRINTERS TO THE QUEEN'S MOST EXCELLENT MAJESTY:
PUBLISHED AT THE GREAT SEAL PATENT OFFICE,
25, SOUTHAMPTON BUILDINGS, HOLBORN.

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MELVILLE, of Upper Harley Street, in the county of Middlesex, Esquire, send
greeting.
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 Eleventh day of May, in the fifth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said John
Melville, Her especial license, full power, sole privilege and authority, that
I, the said John Melville, my exors, admors, and assigns, or such others as I.
the said John Melville, my exors, adiñiors, or assigns, should at any time agree
with, and no others, from time to time and at all times 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 "CERTAIN IMPROVEMENTS IN PROPELLING VESSELS;" in which said
Letters Patent is contained a proviso that I, the said John Melville, shall cause
a particular description of the nature of my said Invention, and in what manner
the same is to be performed, to be inrolled in Her said 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.

page_text: NOW KNOW YE, that in compliance with the said proviso, I have ascer-
tained and set forth the nature of my Invention, and the manner in which it
is to be carried into effect, by the following description thereof, referenco being
had to the Drawings hereunto annexed.
purpose
My Improvements in propelling vessels aro chicfly intended for the ser-
vice of sailing vessels in which steam power is occasionally employed as an
auxiliary. It is very desirable that propellers designed for this
should
be simple in their construction, should occupy but little space over the sides of
the vessel, and should present no obstacle to the progress of the vessel when
their action is not required.
The first part of my Invention consists in a paddle or float applicable to
paddle wheels or to levers put in motion to propel vessels, and so arranged as
to get rid in a great measure of the oblique action of the boards or floats of
tho common paddle wheel, which occasions concussion on the boards or floats
entering the water, and back water on their leaving it. To effect this object
I suspend the board or float on a spindle or axis, which spindle or axis may be
fixed, and the board or float attached to it so as to move on it, or the board or
float may be fixed to the spindle or axis, and move with it; but in either case
the area of that portion of the board or float on either side of the spindle or
axis must be of equal or nearly equal dimensions. It is obvious when a board
or float so suspended is fully immersed in the water, and in motion, that it will
assume a vertical position, and will preserve that position so long as the pressure
on its surface on either side of the spindle or axis is the same. I construct the
board or float in such way that the half of it which is on the lower side of the
spindle or axis shall be heavier or of greater weight than the other half, so as
to make it preponderate; and to limit the effect of the centrifugal force on that
balf I apply a chain or other suitable stop, which can be arranged so as to deter-
mine the angles at which the board or float shall enter or leave the water.
I have found by experiment that if the board or float be allowed to vibrate in
an arc of about ninety degrees a good effect is obtained. An arrangement
of propellers on this plan is shewn in Figures 1 and 2; Figure 1 being a vertical
section and Figure 2 a plan of the same. a is the shaft; b and c arms or levers
radiating in opposite directions from the shaft; and d, d, floats turning upon
spindles e, e, fixed in the outer extremities of the arms. The extent to which
the floats are allowed to vibrate upon their spindles may be regulated by the
chain for the stop g, or any other suitable arrangement, so as to cause the
loats to enter and to leave the water at such angle as may be deemed most
advantageous.

page_text: The second part of my Invention consists in so constructing a paddle wheel
that some of the arms can be turned upon the shaft so as to assume a position
nearly parallel to the other arms, and the whole laid in nearly a horizontal
position, whereby they (the floats) are prevented retarding the vessel's progress
when their action is not required. Figures 3 and 4 shew one arrangement
which I employ for this purpose; Figure 3 being an elevation, and Figure 4 a
plan of the same. a is the paddle shaft, and b, 6, 61, bosses upon the shaft,
the bosses 6' being firmly keyed to the shaft, and the bosses 6" and 8" lying
loose upon the shaft between the bosses b¹; c³, c¹¹, and care arms fixed in the
bosses 6, 6, 6 respectively; and d, d, are the floats or propellers. The
arms are retained in the position shewn in the Figure 3 by keying or bolting
the bosses and 6 to the bosses '; but when the services of the propellers
are not required, by withdrawing the bolts or keys the arms can be brought
into the position shewn by the dotted lines. In lieu of the moveable arms
turning upon the shaft as a centre, they may turn upon pins or bolts passing
through the bosses of the fixed pair of arms, in which case they should be
retained in their position by stays from the fixed arms.
The third part of my Invention consists in employing only a pair of floats or
boards, one on each side of the vessel, which floats may be either fixed to the
arms or levers, or may turn upon spindles, as described under the first head of
my Invention; also the arms on each side of the vessel may be fixed to the
shaft, or the arms on one side of the vessel may be keyed to the shaft, and the
arms on the opposite side of the vessel may be connected to the shaft by a
clutch or other contrivance, so that they can be turned upon the axis and placed
at pleasure parallel to or at right angles to the arms on the opposite side, in
which latter case the floats on each side will enter the water in alternate
succession.
I claim as constituting my Improvements in propelling vessels,
First, floats or boards suspended upon axes or spindles, and vibrating in arcs,
the extent of which is regulated by chains or other suitable stops, as herein
described under the first head of my Invention.
Second, a paddle wheel with moveable arms, as described under the second
head of my Invention.
Third, the employment of a pair of levers on each side of the vessel, arranged
as herein set forth under the third head of my Invention.
In witness whereof, I, the said John Melville, have hereunto set my hand
and seal, this Tenth day of November, in the year of our Lord One
thousand eight hundred and forty-two.
JOHN (L.S.) MELVILLE.

page_text: AND BE IT REMEMBERED, that on the Tenth day of November, in the
year of our Lord 1842, the aforesaid John Melville came before our said Lady
the Queen in Her Chancery, and acknowledged the Specification aforesaid, and
all and everything therein contained and specified, in form abovo written. And
also the Specification aforesaid was stamped according to the tenor of the Statute
made for that purpose.
Enrolled the Eleventh day of November, in the year of our Lord One
thousand eight hundred and forty-two. '