AN IMPROVED CONSTRUCTION OF PADDLE WHEEL
Year: 1865

page_text: LETTERS PATENT to James Jennings McComb, of Liverpool, in the
County of Lancaster, Gentleman, for the Invention of "AN IMPROVED
CONSTRUCTION OF PADDLE WHEEL."-A communication from abroad by
Ephraim Chidester M°Comb, of San Francisco, in the State of California,
United States of America.
PROVISIONAL SPECIFICATION left by the said James Jennings McComb,
at the Office of the Commissioners of Patents, with his Petition, on the
27th September 1865.
I, JAMES JENNINGS MCCOMB, of Liverpool, in the County of Lancaster,
Gentleman, do bereby declare the nature of the said Invention for "AN
IMPROVED CONSTRUCTION OF PADDLE WHEEL," to be as follows:-
This Invention relates to an improved construction of paddle wheel from
which a more effective propelling power may be obtained than from the
wheels in general use. It saves the power which is lost in the violent'
percussion which is inseparable from a rapid perpendicular action against the
water. It does not, therefore, cause that concussion and vertical vibration so
destructive to the boat and inimical to her speed. The boat is also free from
the heavy and retarding friction of the back water. The arrangement of
the floats is such that they concentrate their power or pressure at their outer
ends as it is with the wings of a bird or the blades of an oar, and this is

page_text: directly transferred to the shoulder of the wheel shaft next the boat: The
floats enter the water propelling, and leave the water propelling free from
the impediments of percussion and lift. The action of the wheel is that o
the oar at its best angle gathering its power gradually, and always reaching
into undisturbed water. Upon the wheel shaft are firmly keyed three or
more hubs provided with radial arms for receiving the floats. These arms
set out of line with each other in the direction of the wheel's axis, the object
being that their ends shall correspond with a line drawn at or about an angle
of 45° with the axis. This line of the arms forms an acute-angle with the
side of the boat facing the bow, and an obtuse angle at the opposite or rear
side. The inner edges of the inside arms, that portion where the floats must
find a bearing, are slanted or brought to the proper bevil angle of about 45°,
and the outside edges of the corresponding outside arms are also slanted or
brought to the aforesaid proper bevil angle. with a gradual tapering or falling
off to the ends of the arms. The ends of the arms should not project beyond
the lower edge of the float but be cut tapering from them. The centre arms
have such a bevil and taper on their outside edges. as will afford the desired
bearing for the floats in their central position. The floats are laid through
the entire breadth of the wheel at or about an angle of 45° acute to the side
of the boat facing the bow and correspondingly obtuse at the reverse side; and
they are secured so, that their upper edges will be equidistant from the axis
of the wheel, or parallel with the surface, of the water, and in a straight or
right line.
At their outer_ends the floats are about one-fifth wider than at
their inner ends, the inner edges being convex or crowned, increasing to
the outside. end. The ends, of the floats are convex decreasing from the
outer to the inner edge. These floats when affixed to the arms will present
an oblique concavity running from the outer edge. on the inside to the inner
edge of the outside, and a slight general longitudinal.convexity, and the floats
will project well beyond the arms. The peculiar twist or curves belonging to
this float, after the prescribed form and shape have been attained, must be
produced before the floats are affixed to the arms whether the same be made
of wood or iron. It will follow as a matter of course that the outside arms,
are as much longer than the inside arms as the floats are w wider at that point,
than at the inside. This long angle gathers the water, and concentration,
takes place at the outer ends, and the retarding elements of percussion and
lift, so conspicuous in the wheel in general use are absent in this wheel, and
in their stead the floats act as propellers both when entering and leaving the
otor
"

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Jennings McComb in the Great Seal Patent Office on
the 27th March 1866:
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
JENNINGS MCCOMB; of Liverpool; in the County of Lancaster, Gentleman,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of September,. in the year of our
Lord One thousand eight hundred and sixty-five, in the twenty-ninth year of
Her reign, did for Herself, Her heirs, and successors, give and grant unto
me, the said James Jennings. McComb,. Her special licence that I, the said
James Jennings McComb, my executors, administrators, and assigns, or
such others as I, the said James Jennings McComb, my executors, admi-
nistrators, and assigns, should at any time agrée with,. and no others, from
'time-to time and at all times thereafter during the term therein expressed;
should and lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle of
Man, an Invention for "AN IMPROVED CONSTRUCTION OF PADDLE WHEEL,"
being a communication to him from abroad by Ephraim Chidester McComb,,
of San Francisco, in the State of California, United States of America,.
upon the condition (amongst others) that I, the said. James Jennings
McComb, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office. within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said James Jennings McComb, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and .by the
following statement, reference being had to the Drawing hereunto annexed,
and to the letters and figures marked thereon (that is to say):-
This Invention relates to an improved construction of paddle wheel from
which a more effective propelling power may be obtained than from the
wheels in general use; it. saves the power which is lost in the violent
percussion which is inseparable from a rapid perpendicular action against the
water: It does not, therefore, cause that concussion and vertical vibration so
destructive to the boat. and, inimical to her speed. The boat is also free from

page_text: the heavy and retarding friction of the back water. The arrangement of the
floats is such that they concentrate their power or pressure at their outer ends;
as it is with the wings of a bird or the blades of an oar, and this is directly
transferred to the shoulder of the wheel shaft next the boat. The floats enter
the water propelling and leave the water propelling free from the impediments
of percussion and lift. The action of the wheel is that of, the oar at its best
angle, gathering its power gradually, and always reaching into undisturbed
water.
In the accompanying Drawings Fig. 1 shews the-improved paddle wheel in
side elevation, and Fig. 2 in plan or edge view; Fig. 3 is a diagram shewing
the paddle wheel shaft projecting from the side of a steam vessel, -and-with
one float applied thereto, and brought into edge view'; Fig. 4 is a plan view of
a float detached and laid out flat; and Figures 5 and 6 are diagrams shewing.
the curves which the float takes in the corresponding section lines in Fig. 4;
Fig. 7 is a section shewing the manner of tapering or bevilling the arms
which carry the floats.
A is the paddle wheel shaft, upon which three hubs, a, a, a, are firmly.
keyed; these hubs are provided with radial arms b, b, b, for receiving the
floats B, B. The several arms of the same float are set out of line with each
other, the object being that their ends shall correspond with a line drawn at,
or about an angle of forty-five degrees with the wheel's axis, as indicated, by
the red line in Fig. 3. This line of the arms forms an acute angle with the:
side of the boat looking from the bow, and an obtuse angle with the side;
looking from the stern. The inner edges of the inside arms (that portion:
where the floats must find a bearing) are slanted or brought to the proper
bevil or angle of about forty-five degrees, and the outside edges of the
corresponding outside arms are also slanted or brought to the aforesaid
proper bevil or angle with a gradual tapering or falling off to the ends of the
arms. The ends of the arms should not project beyond the outer edge of the
float, but be cut to a corresponding taper. The centre arms are bevilled and
tapered, as shewn at Fig. 7, in order to afford the desired bearing for the
middle of the floats; these floats are laid through the entire breadth of the
wheel, and being secured to the arms 6 which are set around-the paddle
wheel shaft, as above described, the floats will form an acute angle to the
side of the ship, facing the bow, and a correspondingly obtuse angle at the
reverse side. The floats are so mounted or affixed to their arms that their
inner edges throughout their length will be equidistant or nearly so to the
axis of the wheel. At their outer ends the floats will be from one-fifth to.
one-half wider than at their inner ends, as shewn at Fig. 4. Both. ends.of

page_text: the floats are convex, decreasing from the outer to the inner edge; these
floats, when affixed to the arms, as shewn at Fig. 3, will present an oblique
concavity running from the outer angle 4 on the inside end of the float,
Fig. 4, to the inner angle of the outside end 3, as shewn at Fig. 5, and they
have a slight general longitudinal convexity, as shewn at Fig. 6. The ends of
the floats will moreover project well beyond the arms. The peculiar twist
or curves belonging to this float, after the prescribed form and shape have
been attained, must be produced before the floats are affixed to the arms,
whether the same be made of wood or iron. When mounted or attached to
the arms the outer edges of the floats will form tangents to the circle described
by the inner or leading angles of the float. It will follow as a matter of course
that the outside arms are as much longer than the inside arms as the floats
are wider at that point than at the inside. The prolonged sweep of the
rotating float thus obtained gathers the water, and concentration takes place
at the outer ends, while the retarding elements of percussion and lift, so
conspicuous in the wheel in general use, are absent in this wheel, owing to
the gradual immersion endwise of the floats, and in place of these defects the
floats act as propellers both when entering and leaving the water.
Having now set forth the nature of the Invention of an improved
construction of paddle wheel, as communicated to me from abroad, and
explained the manner of carrying the same into effect, I wish it to be
understood that under, the above in part recited Letters Patent I claim,
applying to paddle wheels diagonal floats, constructed and arranged as above
described.
In witness whereof, I, the said James Jennings McComb, have here-
unto set my hand and seal, the Twenty-sixth day of March, in the
year of our Lord One thousand eight hundred and sixty-six.
J. J. MCOMB. (L.S.)