Improvements in Boat-propelling Apparatus.
Year: 1892

page_text: Date of Application, 22nd Mar., 1892
Complete Specification Left, 15th Dec., 1892-Accepted, 25th Feb., 1893
PROVISIONAL SPECIFICATION.
Improvements in Boat-propelling Apparatus.
A communication from D'ARCY D. GRIERSON, of 54, Church Street, Toronto, in
the Dominion of Canada.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex
Member of the Institution of Mechanical Engineers do hereby declare the nature
of this invention to be as follows:-
The object of the invention is to provide a propelling power specially suitable
for rowing boats and by which the ordinary reciprocating movement of rowing
shall produce a rotary movement, and it consists essentially of a shaft carried in
suitable bearings located preferably at the bottom of the boat, the said shaft
projecting through the stern of the boat and having a propelling wheel or screw
fixed to its end. On this shaft are formed two coarse right and left-hand screws
in such a manner that they connect with each other at each end, with which screws
a dog engages, the said dog being carried on a cross-head suitably supported and
provided with a handle by which it is forced backwards and forwards.
The shaft is preferably made in two portions connected together in any con-
venient manner and at the stern of the boat it passes through a suitable stuffing box
which forms a water tight bearing.
The cross-head is carried on suitable guide rods which preferably form portion
of a light frame fixed to the bottom of the boat.
The dog is provided with a suitable spindle which is suitably journaled in the
cross-head so that it will revolve freely and it fits into or engages with the right
and left hand screws as before mentioned.
A rod or handle is connected to the dog at one end and has a cross handle fixed
to its other end. By pulling or pushing this rod or handle the shaft is caused to
revolve in the desired direction. Assuming that the dog is in the right hand
screw, and the cross-head is being pushed upon, it must, in order that the shaft
shall continue to revolve in the same direction on the return stroke of the cross-
head, be pushed to the point where the right hand screw enters the left hand screw
at which point the dog passes from one screw to the other, and consequently on its
return stroke it continues to revolve the shaft in the same direction. In order to
revolve the shaft in the opposite direction it is merely necessary to change the
direction of the movement of the cross-head.
A. propelling power, such as described can be very easily and cheaply applied to
any class of boats, and in rowing boats the delightful exercise of rowing may be
secured while the boat is being propelled at a much greater speed than can be
secured by the use of ordinary sculls.
Only one operating rod and handle may be provided or for propelling a heavy
boat two or more rods and handles may be provided so that they may all be
simultaneously employed for producing the necessary propelling power.
The rudder may be carried in a light frame shaped so as to support it behind
the propeller and at the same time constitute a guard over the said propeller.
Dated this 22nd day of March 1892,
ALFRED J. BOULT,
Chartered Patent Agent.

page_text: COMPLETE SPECIFICATION.
Improvements in Boat-propelling Apparatus.
A communication from D'ARCY D. GRIERSON, of 54, Church Street, Toronto, in
the Dominion of Canada."
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I. Mech. E., and Chartered Patent Agent, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
The object of the invention is to provide a propelling power specially suitable
for row-boats and by which the ordinary reciprocating movement of rowing shall
produce a rotary movement, and it consists, essentially, of a shaft carried in suitable
bearings located at the bottom of the boat, the said shaft projecting through the
stern of the boat and having a propelling wheel fixed to its end, two coarse right
and left-hand screws being cut or formed on the shaft in such a manner that they
connect with each other at each end, into which screws a dog is fitted, the said dog
being carried ou a cross-head suitably supported and provided with a handle by
which it is forced backwards and forwards; substantially as hereinafter more
particularly explained.
Figure 1 is a perspective view of a portion of the boat showing the improved
propelling power apparatus inserted in position.
Figure 2 is a perspective view of a detail of the apparatus.
Figure 3 is a perspective detail view of the dog and its cross-head.
Figure 4 is a plan of the shaft as it would appear if laid out flat.
In the drawing, A represents a shaft suitably journalled in the bottom of the
boat B. The end of the shaft projects through the stern of the boat and has a
propeller wheel C fixed to it as indicated. This shaft A is preferably made in two
portions and attachably connected as shown.
D is a suitable stuffing box located at the stern of the boat B and forming a
water-tight bearing for the end of the shaft A.
E is a cross-head carried on suitable guide rods F which are preferably made of
a portion of a light frame fixed to the bottom of the boat B.
G is a dog provided with a suitable spindle G which is suitably journalled
in the cross-head E as indicated, so that it will revolve freely. The dog G fits
into or engages with the right and left-hand screws marked a and b, respectively.
H is a rod or handle connected to the dog G, at one end, and having a cross-
handle I fixed to its other end. By pulling or pushing the rod or handle H, the
shaft A is caused to revolve in the desired direction. Assuming that the dog is in
the right-hand screw a and the cross-head E is being pushed upon, it must, in order
that the shaft shall continue to revolve in the same direction on the return stroke of
the cross-head, be pushed to the point where the screw a enters the screw b (see Fig. 4)
at which point the dog passes from one screw to the other, and consequently on its
return stroke it continues to revolve the shaft in the same direction. In order to
revolve the shaft in the opposite direction, it is merely necessary to change the
direction of the movement of the cross-head.
A propelling power, such as described, can be very easily and cheaply applied to
any class of boats, and in row-boats the delightful exercise of rowing may be secured
while the boat is being propelled at a much greater speed than can be secured by
the use of ordinary sculls.
Only one rod is shown with a handle I, but of course it will be seen that for a
heavy boat it may be advisable to duplicate the rod and handle so that the two
parts may be simultaneously employed for producing the necessary propelling
power.
Jis a rudder carried in a light frame K shaped so as to hold the rudder J behind

page_text: the propeller wheel C and at the same time constitute a guard over the said
propeller.
Having now particularly described and ascertained the nature of the said
invention, as communicated to me by my foreign correspondent, and in what manner
the same is to be performed, I declare that what I claim is,-
1. A shaft suitably journalled and having a right and left-hand screw formed on
it in such a manner that the said screws run one into the other in combination with
a dog engaging with the said screws and connected to a cross-head deriving a
reciprocating motion substantially as and for the purpose specified.
2. A shaft supported in suitable bearings at the bottom of the boat and having a
propeller wheel fixed to its end which projects through the end of the said boat and
a right and a left-hand screw formed on the portion of the shaft within the boat the
said screws connecting together at each end in combination with a dog formed on
the end of a spindle journalled in a suitable cross-head which derives a reciprocating
motion from a rod or handle substantially as and for the purpose specified.
Dated this 13th day of December 1892.
W. P. THOMPSON & BOULT,
Agents for the Applicant.