IMPROVEMENTS IN PROPELLING VESSELS
Year: 1854

page_text: LETTERS PATENT to Henry Walduck, of 5, Warwick Court, Gray's Inn,
for the Invention of "IMPROVEMENTS IN PROPELLING VESSELS."
Sealed the 26th September 1854, and dated the 29th July 1854.
PROVISIONAL SPECIFICATION left by the said Henry,Walduck at the
Office of the Commissioners of Patents, with his Petition, on the 29th
July 1854.
I, HENRY WALDUCK, of 5, Warwick Court, Gray's Inn, do hereby declare
the nature of the Invention for "IMPROVEMENTS IN PROPELLING VESSELS" to be
as follows:-
It is well known that in the using of screw and such like propellers the
water in which they move is so acted on as to produce what is called ".
"slip,"
and much of this is considered to arise from the water being put in motion by
the propellers in a direction from the centre of the propeller shaft outwards.
Now, my Invention has for its object to construct the faces of propellers with a
view to counteract this tendency of propellers to put the water in motion in a
direction from the axis of a propeller outwards; and my Invention consists of
making each propeller grooved or fluted on its propelling face or surface, the
grooves or flutes being formed in curved directions, consequently tending to
retain the water, against which the parts of a propeller is for the time being
acting, from moving or being moved or thrown by the propeller in a direction
from the axis of the propeller outwards.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Walduck in the Great Seal Patent Office on the
29th January 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, J, HENRY
WALDUCK, of 5, Warwick Court, Gray's Inn, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of July, in the year of our Lord
One thousand eight hundred and fifty-four, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Henry Walduck, Her special licence that I, the said Henry Walduck, my
executors, administrators, and assigns, or such others as I, the said Henry
Walduck, my executors, administrators, and assigns, should at any time agree
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 "IMPROVEMENTS IN PROPELLING
VESSELS," upon the condition (amongst others) that I, the said Henry
Walduck, by an instrument in writing under my hand and seal, should par-
ticularly 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 Henry Walduck, lo hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof (that is to say):-
It is well known that in the using of screw and such like propellers the
water in which they move is so acted on as to produce what is called "slip,"
and much of this is considered to arise from the water being put in motion by
the propellers in a direction from the centre of the propeller shaft outwards.
Now, my Invention has for its object to construct, the faces of propellers with
a view to counteract this tendency of propellers to put the water in motion in
a direction from the axis of a propeller outwards; and my Invention consists of
making each propeller grooved or fluted on its propelling face or surface, the
grooves or flutes being formed in curved directions, consequently tending to
retain the water, against which the parts of a propeller are for the time being

page_text: from the axis of the propeller outwards.
by the propener m a anfection
Having thus stated the nature of my said Invention, I will proceed to
describe the manner of performing the same.
DESCRIPTION OF THE DRAWING.
Figure 1 shows a front and back view and a section of a propeller, consisting
of two blades, each being a portion of a screw; but in place of the faces or
propelling surfaces thereof being plain, they are made with grooves, according
to my Invention. Figure 2 shows a front and back view and also a section
of another form of propeller, with two blades, the propelling surfaces of which
are made with grooves; and Figure 3 shows a front, back, and edge view, and
also a section, of another propeller, with another form of propelling blades,
which vary from a true screw, as shown, each blade consisting partly of a
portion of a cone, which in place of being plain on the face or propelling
surface is grooved, according to my Invention. I would state that I have given
these three forms of propellers as examples, in order to show that, although
the form of the propeller blade may be varied, each form is capable of being
made with grooves on the faces or propelling surfaces, according to my Inven-
tion. I would also state, that although I have only given these three
examples of forms of blades of propellers I do not confine myself thereto; for
I wish it to be understood that my Invention does not depend on the form or
number of the blades used in constructing a propeller, but in forming the
propeller blades, whatever be the form or number thereof, with grooves on the
faces or propelling surfaces; and therefore, although I have not shown pro-
pellers with other than two blades, or with blades of an increasing pitch
screw, or with flat blades, or blades of other forms, I have not done so simply
because a workman will readily, from the description herein given of my
Invention, apply my improvements when making other forms of propeller
blades than those shewn; and I would state that the number of grooves
formed in the propelling surface of a propeller blade, as also their depth, form,
and direction, may be varied. I, however. believe the arrangements shown to
be the best. as far as my experiments have gone. In Figures 1 and 2, each
groove, from its commencement to the end, retains the same distance from the
shaft; but in Figure 3, the grooves come nearer to the propeller shaft at their
back ends than at their forward ends; and I prefer, when the propeller blades
are of a conical form, so to arrange the grooves.
Having thus described the nature of my Invention, and the manner of

page_text: performing the same, I would have it understood that what I claim is, the
the construction of the blades of propellers with grooves on the propelling
surfaces.
In witness whereof, I, the said Henry Walduck, have hereunto set my
hand and scal, this Twenty-seventh day of January, in the year of
our Lord One thousand eight hundred and fifty-five.
-Witness,
FRED HARRIS.
H. WALDUCK. (L.B.)