IMPROVEMENTS IN THE CONSTRUCTION OF PROPELLERS AND IN THE ARRANGEMENT OR METHOD OF FITTING THEM IN ESSELS FOR THE PROPULSION THEREOF.
Year: 1874

page_text: LETTERS PATENT to Joseph Betteley, of Lime Street, in the City of
London, Marine Architect, for the Invention of "IMPROVEMENTS IN
THE CONSTRUCTION OF PROPELLERS AND IN THE ARRANGEMENT OR METHOD OF
FITTING THEM IN ESSELS FOR THE PROPULSION THEREOF.
Sealed the 26th June 1874, and dated the 3rd January 1874.
PROVISIONAL SPECIFICATION left by the said Joseph Betteley at the
Office of the Commissioners of Patents, with his Petition, on the
3rd January 1874.
I, JOSEPH BETTELEY, of Lime Street, in the City of London,
Marine Architect, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE CONSTRUCTION OF PROPELLERS AND IN THE ARRANGE-
MENT OR METHOD OF FITTING THEM IN VESSELS FOR THE PROPULSION THEREOF," to
be as follows :—
This Invention relates firstly to improvements in the construction of
propellers whereby they are stronger and more suitable to withstand
concussion than those now in use. According to this first part of my

page_text: Invention I form or shape the blades from wrought iron or steel under a
steam or other hammer, each blade being formed separately or in pairs,
with a narrow neck and with or without eyes, to fit into a casting of iron
or steel to form a circular boss, the casting being effected in the usual
manner after the blade necks have been arranged in the mould into
which the fluid metal is run.
The second part of my Invention relates to arranging or fitting such
propellers in separate apertures in the stern of a vessel, and at such a
distance apart, but upon the same shaft, that the water from the foremost
one does not interfere with the action of the hinder propeller. By this
means I am enabled to adopt screws of such dimensions that the vessel
can be propelled when in ballast trim or in light draught of water.
I form the dead wood parallel for a distance forward to receive two or
more separate screws in it upon the same shaft, and preferably in separate
apertures to admit of free access of water to the fore parts of the 1
screws.
In some cases I employ one screw in an aperture in the dead wood
and the additional one outside the stern post, or it may be beyond the
rudder. This outside or aft propeller is so arranged that the action of
the rudder is not interfered with, but I purpose terminating the rudder
just above the shaft, and to fit a false rudder or step piece to the stern
post to form not only an extension of the keel but to support the shaft
at its outer end.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Betteley in the Great Seal Patent Office
on the 3rd July 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
BETTELEY, of Lime Street, in the City of London, Marine Architect,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria by Her
Letters Patent bearing date the Third day of January, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Joseph Betteley, Her special licence
that I, the said Joseph Betteley, my executors, administrators, and
assigns, or such others as I, the said Joseph Betteley, 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 THE CON-
STRUCTION OF PROPELLERS AND IN THE ARRANGEMENT OR METHOD OF FITTING THEM
IN VESSELS FOR THE PROPULSION THEREOF," upon the condition (amongst
others) that I, the said Joseph Betteley, 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 Joseph Betteley, do hereby
declare the nature of my said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, reference being had to the
Drawings hereunto annexed, that is to say :-
The first part of my Invention relates to arranging or fitting pro-
pellers in separate apertures in the stern of an iron vessel, and at such a
distance apart, but upon the same shaft, that the water from the foremost
one does not interfere with the action of the hinder propeller. By this

page_text: means I am enabled to adapt screws of such dimensions that the vessel
can be propelled when in ballast trim or in light draught of water.
I form the dead wood parallel for a distance forward to receive two or
more separate screws in it, upon the same shaft, and preferably in separate
apertures, to admit of free access of water to the fore parts of the
screws.
This first part of my Invention will be clearly understood by reference
to Figures and 2 of the accompanying Drawings, which show the after
end of an iron or steel vessel. A, A, are two propellers with two blades,
one preceding the other, placed within an iron frame in the dead wood,
as shown, with an iron stanchion B to support the shaft.
Figure 3 shows the after part of a vessel, also with two double-bladed
screws A, A, placed within the iron frames, but with a broad upright or
partition B, by which the two screws are kept sufficiently apart to
prevent one working in the back water of the other.
Figure 4 is a plan showing the after frame with parallel sides, in the
spaces of which the screws work. The apertures in the vessel are shown
much elongated compared with ordinary screw apertures, and this, with
my arrangement of small diameter blades, ensures the constant sub-
mersion of the blades when the ship pitches or lifts in rough weather, a
and also when the ship is in ballast. By this means the screw propellers
are never exposed, and they work in denser water than is possible with
large diameter blades, consequently loss of power, variations in the rate
of speed, and other inconveniences are obviated, and a positive bite by
the blades upon the water to propel the ship at all times while the engine :
is at work can be effected.
Figure 5 shows the after part of a vessel with two propellers A, A,
each having only a single blade, one arranged in advance of the other,
as shown, to enable the water to get at them in an effectual manner, and
also placed in an iron frame, as in the previous Figures; in this case the
partition or upright B may be dispensed with.
In some cases I employ one screw in an aperture in the dead wood,
and the additional one abaft the rudder. This outside or aft propeller is
so arranged that the action of the rudder is not interfered with, but I
purpose terminating the rudder just above the shaft, and to fit a bracket a

page_text: to the stern post and extension of the keel to form a support to the
screw shaft, on the outer end of which the propeller is placed.
I form the ship with the after end in the ordinary manner, the keel
extending beyond the stern post, to which I attach a bracket or support
for the after end of the screw shaft. This will be understood by reference
to Figure 6, which shows the after end of an iron ship with its keel a
extended beyond the stern post b, which extension carries a bracket c
for the support of the after end of the screw shaft d, and which is also
attached to the stern post. The screw shaft & carries two propellers A, A,
one of which is placed in the dead wood in the fore part of the stern
post, and the other abaft the rudder. The piece beyond the bracket
prevents the after screw becoming entangled by ropes or other debris
over which the vessel may pass, and also prevents the after screw
getting injured should the vessel touch the ground while in shallow
water:
Figure 7 is a sectional view of the stern of a vessel with a four-bladed
screw arranged in an elongated aperture according to my Invention.
In the forgoing description of my arrangements of screw propellers in
separate apertures I have referred only to one or to two blades being
upon the same boss, but it will be understood that three or any other
desirable number of blades as propellers can be cast into the same boss
as forming my Invention, so long as the blades represent a screw
of small diameter and large surface area for acting upon or against the
water, such screws or propellers being arranged upon the same shaft and
in separate apertures, or one in an aperture and one beyond the rudder
post, as herein-before particularly set forth and shown, the distance
between the two screws as propellers also being such that the water from:
the first has as little influence as possible upon the feed of water to the
second screw as a propeller.
The next part of my Invention relates to improvements in the con-
struction of propellers, whereby they are stronger and more suitable to
withstand concussions than those now in use. According to this part of
my Invention I form or shape the blades from wrought iron or steel
under a steam or other hammer, each blade being formed separately or
in pairs with a narrow neck, and with or without eyes, to fit into a
casting of iron or steel to form a circular boss, the casting being effected

page_text: in the usual manner after the blade necks have been arranged in the
mould into which the fluid metal is run.
This part of my Invention will be clearly understood by Figure 8,
which shows an elevation of two blades A, A, upon separate bosses B¹, B',
these being upon a shaft d, and screwed up thereon by the nut D when
the relative positions of the two blades have been decided upon; the
bosses may however be keyed upon the shaft in the usual manner. The
blades are of wrought iron or steel previously shaped (preferably by
steam hammer) and curved; they are broad, and take well over the
exterior of the boss, in which an eye, neck, or projection E (shown in
Figures 9, 10, and 11) is held by the nave of metal being cast round or
over it when in a mould.
The blades are arranged at a distance apart upon the shaft, and the
area of the surface of each is about equal to one-half that of an ordinary
screw blade for a given size of ship, so that when a number, say four,
of my form of blades is affixed in the stern of a vessel the area of the
whole is equal or near to the area of the blades of an ordinary propeller.
By that means I am enabled to propel a vessel with a less amount of
"slip of screw " than by any present method, the water being taken
hold of with better effect by several small broad blades than with a few
large narrow blades. The blades if desirable may be arranged close
together.
Having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I claim,-
First. Making and fitting an elongated frame of open form extending
from the stern post forward and in the dead wood of an iron or steel
ship, with a partition or stanchion within it to form two apertures or
ports, in each of which screw propellers can be arranged as shown.
Secondly. The propulsion of iron or steel vessels by propellers with
two blades, one blade preceding the other, and placed within an iron
frame with a partition between them, as shown in Figures 1 and 2 for
the purposes set forth.
Thirdly. The propulsion of iron and steel vessels by propellers arranged
with single blades on separate bosses in separate apertures, but upon the
same shaft, in the dead wood of the ship, as shown in Figure 5.

page_text: Fourthly. I claim the propulsion of iron or steel vessels by two pro-
pellers fitted to the after part, as described with reference to Figures 6
and 7, one of them being placed in an iron frame before the stern post
and the other abaft the rudder, with the rudder terminating above the
screw shaft, and with the ship's keel extending to or beyond the after
propeller, as described and shown for the purposes set forth.
Fifthly. I claim the construction of screw propellers by the com-
bination of wrought iron or steel blades with cast metal bosses, such
blades being arranged singly or in pairs in or to the same boss, in the
manner described and shown in the Drawings.
In witness whereof, I, the said Joseph Betteley, have hereunto
set my hand and seal, this Second day of July, One thousand
eight hundred and seventy-four.
JOSEPH BETTELEY. (L.S.)
Witness,
H. GARDNER,
Robertson, Brooman & Co.,
Patent Agents,
166, Fleet Street,
London.