IMPROVEMENTS IN PROPELLING SHIPS OR SIMILAR VESSELS
Year: 1883

page_text: LETTERS PATENT to Christopher Crosier, of Gateshead in the County of
Durham, Engineer for an Invention of IMPROVEMENTS IN PROPELLING
SHIPS OR SIMILAR VESSELS, a communication from Andres Keating a person
resident at Valparaiso in the Republic of Chili in South America
PROVISIONAL SPECIFICATION left by the said Christopher Crosier at the
Office of the Commissioners of Patents on the 5th October 1883.
"
CHRISTOPHER CROSIER of Gateshead, in the County of Durham, Engineer
"IMPROVEMENTS IN PROPELLING SHIPS OR SIMILAR VESSELS (a communication
to me by Andres Keating, a person resident at Valparaiso in the Republic of
Chili in South America)
According to this invention the ship or other similar vessel is fitted at after end
with one or more cylindrical pipes open at their outer ends and fitted at their inner
ends against a bulkhead with stuffing boxes to make them water tight. These
pipes may be either parallel to the keel of the vessel or may be parallel with the
fore and aft centre line of the vessel laterally or may be at any angle thereto. In
these cylindrical pipes are closely fitted hollow rams working through the stuffing
boxes on bulkheads with any fixed reciprocating stroke. Both ends of these rams
are closed and to the inner ends are connected the prime mover which may be a
steam engine or any other motive power and the connection may be either direct
or by gearing or other mechanical equivalent which will give the rams a quicker
motion than the prime mover itself.
In order to enable the ship or vessel to be propelled astern it is proposed to fit in
the ordinary manner a small auxiliary propeller which may be either worked in
conjunction with the rams or used only when it is desired to go astern. This
auxiliary propeller is worked from the same prime mover as the rams and is
arranged so that it can be drawn into a recess when not in use to avoid retarding
the speed of the ship or vessel.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Christopher Crosier in the Patent Office on the 5th April 1884.
CHRISTOPHER CROSIER of Gateshead in the County of Durham Engineer.
IMPROVEMENTS IN PROPELLING SHIPS OR SIMILAR VESSELS (a communication to
me from abroad by Andres Keating a person resident at Valparaiso in the
Republic of Chili in South America)
According to this invention the Ship or other similar vessel is fitted at after end
with one or more cylindrical pipes open at their outer ends and fitted at their inner
ends against a bulkhead with stuffing boxes to make them watertight. These
pipes may be either parallel to the keel of the vessel or may be parallel with the
fore and aft centre line of the vessel laterally or may be at any angle thereto. In
these cylindrical pipes are closely fitted hollow rams working through the stuffing
boxes or bulkheads with any fixed reciprocating stroke. Both ends of these rams
are preferably closed but the inner ends may be open in like "trunks" and they
are connected to the prime mover which may be a steam engine or any other
motive power and the connection may be either direct or by gearing or other
mechanical equivalent which will give the rams a quicker motion than the prime
mover itself
When at the extremity of their outward stroke I prefer that the rams shall
project from the pipes the full length of their stroke so that when at the extremity
of their inward stroke their outer ends just enter the ends of the stern pipes
In order to enable the ship or vessel to be propelled astern it is proposed to fit in
the ordinary manner a small auxiliary propeller which may be either worked in
conjunction with the rams or used only when it is desired to go astern This
auxiliary propeller is worked from the same prime mover as the rams and may be
arranged so that it can be drawn into a recess when not in use to avoid retarding
The accompanying drawings illustrate the mode of carrying out the invention in
practice with two rams making alternate strokes and showing a small auxiliary
propeller for driving the vessel astern
Figure 1 shews a longitudinal view partly in section of the after portion of a
vessel Figure 2 a sectional plan of same. The same letters refer to corresponding
parts on both figures and Figure 3 a stern view-A. A¹ are the cylindracal pipe
fitted to bulkheads B. B¹ (formed in the structure of vessel) with stuffing boxes at
their inner ends C. C' are the rams C being at the extremity of its inward stroke,
ready to make the outward stroke, and C at the extremity of its outward stroke,
ready for making the inward stroke DD are the rods through rams attaching
them by means of coupling rods EE (working through proper guides F F.) to
connecting rods G G which take hold of cranks H H on a transverse shaft,
working in bearings in a strong bed plate fixed in engine room having upon it
spur pinions J J gearing into spur wheels K K on shaft of prime mover the
different diameters of those wheels and their pinions determining the speed of the
rams relatively to that of the prime mover. A bevil wheel L on transverse shaft
drives a similar bevil wheel M on end of screw propeller shaft N working in
suitable bearings and through the stern tube O and drives the propeller P when
required. The bevil wheel M is fitted so as to slide into and out of gear with L by
means of a clutch lever or screw
In alternative arrangements it is proposed to fit three rams namely, one central
ram and two side rams the united areas of which are equal to that of the central

page_text: ram and which make alternative strokes with it. Or in another arrangement four
rams may be used two working alternate strokes with the other two.
Having now described my invention and illustrated one mode in which it may
be carried into practical application I declare that what I consider novel and there
fore claim as secured to me by the hereinbefore in part recited Letters patent is as
follows namely.
Firstly. The application of hollow reciprocating rams to propel a ship or other
similar vessel acting on their outward stroke against the resistance of the
surrounding water working through and out of cylindrical pipes constructed in
or fitted to the vessels stern substantially as shewn and described.
Secondly. A propelling apparatus for ships or similar vessels comprising hollow
reciprocating rams acting on their outward stroke against the resistance of the
surrounding water, cylindrical pipes constructed in or fitted to the vessels stern
and through which said hollow rams work connecting rods by which motion may
be communicated to said hollow rams from a steam engine or other prime mover
either direct or by suitable gearing, and an auxiliary screw propeller with shafting
connecting same to said steam engine or other prime mover and whereby the ship
or vessel may be caused to go astern when required the whole arranged and
operating substantially as shewn and described.
In witness whereof I the said Christopher Crosier have hereunto set my hand
and seal this fourth day of April in the year of Our Lord one thousand eight
hundred and eighty four
CHRISTOPHER CROSIER (LS)