IMPROVEMENTS IN PROPELLING SHIPS OR VESSELS, AND IN THE PROPELLERS TO BE EMPLOYED THEREIN
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by Charles Mathew Barker at the
Office of the Commissioners of Patents, with his Petition, on
the 10th January 1872.
I, CHARLES MATHEW BARKER, of 12, Kennington Park Road, in the
County of Surrey, Engineer, do hereby declare the nature of my said
Invention for "IMPROVEMENTS IN PROPELLING SHIPS OR VESSELS, AND IN THE
PROPELLERS TO BE EMPLOYED THEREIN," to be as follows:-
This Invention relates to a novel system or mode of propelling ships
or vessels, and to a peculiar construction and arrangement of propeller
to be employed therein, whereby the power is applied in a direct and
more efficient manner than heretofore.
According to this Invention I propose to employ a peculiarly con-
structed propeller revolving within a surrounding case placed in a
suitable aperture in the dead wood or run of the vessel; this case is
open at its stern end, and has apertures at its opposite end, and through
these ends currents are produced that propel the vessel forward or astern
as required. This case is by preference in the form of an open-ended

page_text: cylinder, but with one end partially closed, and made hemispherical and
having apertures thercin, an axial orifice being also provided in which
revolves the propeller shaft which carries the propeller. This propeller
is in form similar to the case, but is of less diameter, being a short open
ended cylinder with a partially closed hemispherical end, which is keyed
on the shaft. This end has apertures for admission of the water into the
annular space between the propeller and the case in which it revolves.
On the periphery of the propellers there are fixed two or more (but by
proference three) segments of screw blades which increase in depth from
the axial end to the point where they join the parallel cylindrical space
to which they conform. This propeller may be made to overhang the
end of the shaft, or the shaft may be continued into and be centred in
the storn post. On motion being imparted to the propeller, two separato
currents, namely, an inner and an outer one, are produced in opposite
directions, but both in line with and parallel to the axis of the propeller.
The inner current moves in the direction of the vessels forward course,
and this current enters the inner circumference of the propeller, and
passes through the apertures in the hemispherical end thereof into the
annular space before mentioned. The screw blades then reverse the
direction of this current, which now becomes the outer one, by expelling
the water in the direction of the stern of the vessel in the form of a
rotatory annular current, such current being perfectly axial to the keel,
consequently exerting the power applied directly to the propulsion of the
vessel. On reversing the motion of the propeller, the outer current will
be expelled through the openings in the front or hemispherical end of
the outer casing, which opening or openings may or may not be in com-
munication with directing pipes, and be provided or not with adjustable
stop valves as found requisite for the purpose of manoeuvering the
ship.