Year: 1888

page_text: Date of Application, 1st Feb., 1888
Complete Specification Left, 1st Nov., 1833
Complete Specification Accepted, 7th Dec.. 1838
I JOHN MOORE of Belfast in the county of Antrim, Ireland Smpowner do hereby
declare the nature of this invention to be as follows:-
This invention comprises arrangements in placing and fitting screw propellers
to steam vessels whereby greater useful effect can be obtained by them under
varying conditions of weather and depth of water.
According to one arrangement I place, in addition to the usual single propeller
placed in a screw aperture between the stern and the rudder posts of such steam
vessels, a second or auxiliary screw propeller as low down near the keel as circum-,
stances and the construction of the ship or vessel will permit.
The shafts of the two propellers may be in the same vertical plane and parallel
to each other.
The auxiliary propeller may be partly protected by the overhanging stern frame
and rudder or it may be carried out through a prolongation or boss on the heel
of the stern frame forming a support for the propeller shafting.
In the latter arrangement the auxiliary propeller may be of large diameter.
The auxiliary propeller may be driven from the main engine shafting by means of
toothed, or by frictional or other suitable gearing worked by the main engines or
I may employ separate engines for each. The auxiliary gearing is to be discon-
necting and the main shafting is also to be disconnecting at a point abaft and
clear of the auxiliary gearing so that both or either one or other of the propellers
can be driven at will.
By preference 1 construct the propellers with two blades each so that when the
main propeller is at rest it can be fixed by means of suitable locking apparatus
of ordinary construction placed on the shafting inside the vessel so that the blades
are kept in a vertical position to minimize their resistance when the vessel is
progressing through the water.
Similarly when the main propeller is working, the gearing for driving the
auxiliary propeller can be disconnected and the said propeller may then be secured

page_text: in a horizontal or other desired position to minimize its. draft and consequent risk
of touching the ground when in shallow water.
Preferably I make each propeller of right and left handed pitch respectively or
both may be right hand or left hand pitch actuated by suitable gearing and I do
not limit myself to the precise arrangements herein described but may vary the
position and number of the propellers and may place the auxiliary propeller or
propellers on either side of the main propeller and either above or below it and
do not necessarily limit myself to placing it or them abaft, or astern of the main
propeller.
The shafts may be inclined both in the vertical and horizontal planes and be
driven at unequal speeds according to the respective diameter and pitch of the
propellers.
Dated this 1st day of February 1888.
POPPLEWELL, COLTON & Co.,
Agents for the Applicant.

page_text: I JOHN MOORE of Belfast in the County of Antrim Ship Owner, 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:
This invention comprises arrangements in placing and fitting screw propellers
to steam vessels whereby greater useful effect can be obtained by them under
varying conditions of weather and depth of water.
The accompanying drawing shews a side elevation of a ships stern fitted with
an arrangement of propellers whereby I connect the engines with the propeller A
placed as low down near to the keel as circumstances and the construction of the
ship will allow so that the blades are clear of the rudder and work below the
level of the keel in dense water.
It may be a two bladed propeller or the number of blades may be varied if
necessary, the blades being well thrown back to clear the rudder, and when dis-
connected from the engines, it can, by suitable locking apparatus, be fixed in a
horizontal position to minimise its draft, and prevent its touching the ground
when in shallow water.
.
I also use a second propeller B placed in the ordinary screw aperture between
the stern and the rudder posts, or in lieu of this second propeller I may place
at about the same height à separate propeller on each side of the stern post after
the manner of twin screws.
Such length of shafting as may be required for this purpose, can be driven by means
of toothed or frictional or other suitable gearing, worked by the shafting connected to
the engines, or I may employ separate engines for each propeller. Such gearing can
be arranged to be disconnecting, and the engine shafting to be disconnecting at a
point abaft, and clear of the gearing, so that either one or the other, or all the
propellers can be driven at will.
I construct the upper propeller B with two or more blades and when at rest it may
be fitted in a vertical position to minimise its resistance when the vessel is progressing
through the water, by means of locking apparatus of suitable construction placed on
the shafting inside the ship, or it may be left free to revolve when disconnected.
The propellers may be right and left hand pitch respectively, or both can be right
hand or left hand pitch, but I do not bind myself to the precise arrangement herein
described, but may vary the number and position of propellers, and may place the
lower propeller either at the bow or stern of the vessel, with either a single or twin
Screw propeller placed above it, either at one end or both ends of the vessel, or I can
use two propellers placed at the level of the keel.
The shafts may be inclined both in the vertical and horizontal planes, and can be
driven at unequal speeds according to the respective diameter and pitch of the
Dronellers

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is -
First In the propulsion of steam vessels the employment of a propeller or twin
propellers so placed that its or their blades work below the keel, in combination with
a propeller placed in the stern aperture, or with twin propellers, such system of
propellers being so arranged that they may be driven separately or collectively,
substantially as described.
.
Second: The method of mounting and combining the use of one or more propellers
substantially as described with reference to the accompanying drawings.
Dated this 1st day of November 1888.
POPPLEWELL, COLTON & Co.,
17 & 18, Southampton Buildings, London, W.C.,
Agents for the Applicant.