AN IN- PROVEMENT IN SCREW PROPELLERS
Year: 1857

page_text: LETTERS PATENT to Stanislas Gaudrion, of 53, Chancery Lane, London,
and of Paris, in the Empire of France, for the Invention of "AN IN-
PROVEMENT IN SCREW PROPELLERS."-(A communination from Mr. Jules
Vergne.)
Sealed the 29th September 1857, and dated the 26th June 1857.
PROVISIONAL SPECIFICATION left by the said Stanislas Gaudrion at the
Office of the Commissioners of Patents, with his Petition, on the
26th June 1857.
I, STANISLAS GAUDRION, of 53, Chancery Lane, London, and of Paris, in
the Empire of France, do hereby declare the nature of the said Invention for
"AN IMPROVEMENT IN SCREW PROPELLERS," to be as follows:-
'My Invention relates to improvements in screw propellers for vessels, which
improvements are intended to prevent the molecules of water struck by the
screw from passing towards the periphery by yielding to the centrifugal force,
and from producing prejudicial eddies. I obtain these results by means of
grooving or fluting the surface of the screw, instead of using a plain surface
as usual. By fluting the surface of the screw, I mean making grooves in the
body of the metal, or the grooved surfaces may be produced by means of
raised ribs affixed to the screw surface, which ribs may be either inclined or
curved towards the centre of the screw, or the reverse, or stand at right angles
to the face of the screw. I form these grooves on the surface of the screw
either in the direction in which the screw is generated, or they may be at

page_text: _angles, or inclined thereto, as may be most desirable. In making flutings or
projecting faces in the solid of, the screw I prefer that the screw face should
lean forward a little, in order that rising surfaces may be formed thereon, in
the form of a series of steps rising one above the other, as they approach from
the centre towards the periphery.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Stanislas Gaudrion in the Great Seal Patent Office on the
24th December 1857..
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, STANISLAS
GAUDRION, of No. 53, Chancery Lane, London, and of Paris, in the Empire
of France, send greeting.
.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date. the Twenty-sixth day of June, in the year of our Lord
One thousand eight hundred and fifty-seven, in the twenty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Stanislas Gaudrion, Her special licence that I, the said Stansilas Gaudrion,
my executors, administrators, and assigns, or such others as I, the said Stanislas
Gaudrion, 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
terin 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 IMPROVEMENT IN SCREW
PROPELLERS, a. communication from Mr. Jules Vergne; upon the con-
dition (amongst others) that I, the said Stanislas Gaudrion, 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 Stanislas Gaudrion, do 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, reference being had to the Sheet of Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say):―
This Invention relates to improvements in screw propellers for vessels. These
improvements are intended to prevent molecules of water.struck by the screw.

page_text: from rolling on to its surface when the water yields to the centrifugal force,
and from producing injurious eddies. I have obtained this result by means
of a grooved screw; by a grooved screw, I mean that the surface of the
ordinary screw, instead of being smooth, has straight, curved, or irregulār
grooves i, i, (Figs. 1 and 2) hollowed out of the metal, or formed by means of
ribs or ridges connected to it, these grooves being made in the same direction
as the generators of the screw, or at any angle thereto (see Fig. 5, which is a
section through a,b; Fig. 6, section through c, d; Fig. 7, section through
m, n; Fig. 8, section through p, q; all four being sections of parts such as on
Fig. 2); the said grooves i, may be parallel to each other, or at any angle to
each other.
Fig. 2 represents the projection of a grooved screw on a plane perpendicular
to the axis of the shaft h. This screw which, has only two arms or propelling
surfaces, can, with the application as above mentioned, have three, four, or six
arms, each of which is furnished with projections i, whatever be its or their
thread and diameter. The projections i, i, are joined to the screw in the
direction of the intersection of the helical surface by 'that of cylinders, whose
diameters vary and which have for a common axis the axis of the shaft of the
screw itself. These ribs or projections have for a base projecting flanches of
suitable height and width, their length is equal to the breadth of the pro-
pelling surfaces. These ridges or projections, which are raised above the
general surface of the screw, as shown in the section through a, b, (Fig. 5,)
may be inclined at any angle on the surface, see sections through c, d, m, n,
(Figs. 6 and 7).
Fig. 3 represents a section of a grooved screw through a plane per-
pendicular to the axis of the shaft, cutting the boss into two equal parts.
This screw is composed of portions k, k, of the ordinary screw cut on the face
in concentric steps in lieu of the projections i, i; these portions of the primitive
screw are arranged at various heights, above or below a horizontal plane
marked x, y, and are connected together by metal faces, represented vertically
at e, f, e, f, Fig. 3, which perform the duty of the projections i, i, Figs. 1
and 2, and are determined like those projections.
Fig. 4 represents the projection d', of an ordinary screw, having two arms
on a plane parallel to the axis of the shaft; t, blades of the screw; g, boss;
h, shaft. In a word, the idea on which the propeller forming the object of the
present Invention is based, consists simply in the breaking of all or part of the
mass of water struck by the ordinary screw, and this breaking is effected
cither by projections on or by hollows made in the ordinary screw, as herein-
before described.

page_text: It is understood that the scale of the annexed Drawings vary with the size
of the propellers.
Having described the nature of this Invention, and the manner of performing
the same, I wish it to be understood that I do not limit myself to the forms of
screw shown in the Drawing; but that what I claim as the Invention to be
protected by the herein-before in part recited Letters Patent is, all projections,
ribs, notches, steps, formed on or affixed to any form and size of screw what-
ever, whereby to prevent the formation of eddies or of centrifugal currents of
water produced by the centrifugal force, as herein-before described.
In witness whereof, I, the said Stanislas Gaudrion, have hereunto set 1
my hand and seal, this Twenty-first day of December, in the year of
our Lord One thousand eight hundred and fifty-seven.
S. GAUDRION. (L.S.)