AN IMPROVED CONSTRUCTION OF IRON STEAM Ships for Trading PurpoSES.
Year: 1872

page_text: LETTERS PATENT to Alfred Robert Davidson Mackenzie, of No. 14,
St. James's Square, in the County of Middlesex, a Captain in Her
Majesty's Bengal Cavalry, for the Invention of "AN IMPROVED
CONSTRUCTION OF IRON STEAM Ships for Trading PurpoSES.
PROVISIONAL SPECIFICATION left by the said Alfred Robert Davidson
Mackenzie at the Office of the Commissioners of Patents, with his
Petition, on the 3rd April 1872.
66
I, ALFRED ROBERT DAVIDSON MACKENZIE, of No. 14, St. James's
Square, in the County of Middlesex, a Captain in Her Majesty's Bengal
Cavalry, do hereby declare the nature of the said Invention for AN.
IMPROVED CONSTRUCTION OF IRON STEAM SHIPS FOR TRADING PURPOSES," to be
as follows:-
My Invention has for its object an improved construction of iron
steam ships for trading purposes, which, while it affords a large carrying.
capacity in proportion to the dimensions and cost of the vessel, requires a

page_text: lessened propelling power, and at the same time combines the maximum
strength of hull, greatest attainable degree of safety in bad weather, with
ease of motion, minimum of pitching, reduced liability of engines to race,
and freedom from accumulation of deck water.
For this purpose I construct the hull of the vessel of a closed or box-
like form, that is, with an iron deck forming a continuation of the sides,
the transverse section amidships being approximately rectangular, termi-
nating fore and aft in the usual stem and stern posts, the deck being,
however, made considerably narrower towards both ends than in vessels
of usual construction, while the stern part overhangs the stern post only
sufficiently to protect the rudder and screw propeller or propellers, as
the case may be. At each end of the vessel is formed a closed air
chamber, and the entire remaining capacity of the hull, with the excep
tion of the engine and boiler rooms and water ballast chambers, is
rendered available for stowage of merchandize, a raised iron deck-house
being provided amidships for containing the cabins for officers, crew, and
passengers, for store and sail rooms, and for steering gear.
This deck-house has no side openings communicating with the cabins
and other compartments except for lights, access being gained thereto
and to the engine and boiler rooms below it through its upper deck.
The deck of the hull is entirely without bulwarks, and when loaded
the vessel has a low freeboard, so that it offers comparatively little
obstruction to the waves, which are free to wash over it, the raised deck-
house affording at the same time perfect safety and comfort to the crew
and passengers.
Over the bow air chamber is provided a raised anchor deck, the
anchors being by preference worked from capstans or winches in or
adjoining the deck-house, from which the cables pass along to the bows
over the deck.
If desired, the ordinary cargo hatchways may be extended, and a
portion of the deck may be sunk sufficiently to contain the hauling
gear, such as winches and cranes, for loading and unloading the vessel,
which extended hatches with sunken deck gear below are closed in
with water-tight covers as required.
With this construction of steam ships it is proposed to have the
necessary gangways, ladders, and railings for giving safe access to every
part as required:

page_text: As an additional element of safety, this improved arrangement of
steam ship would facilitate the formation of extended buoyant air
chambers along the upper sides or the deck of the ship, or both if
required, and such chambers may be simple extensions of the ordinary
water ballast chambers.
Another advantage of this improved construction of steam ship.
would be that in consequence of the comparatively reduced bulk of the
ends of the ship and their air-tight construction, together with their
reduced weights, great facilities would be afforded for so trimming the
vessel as to give ready access to the outer surface of the hull at either
end when afloat, and this alteration of trim can be effected by filling a
water-tight compartment or introducing weight at either end, as may be
required.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alfred Robert Davidson Mackenzie in the Great
Seal Patent Office on the 2nd October 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
ROBERT DAVIDSON MACKENZIE, of No. 14, St. James's Square, in the
County of Middlesex, a Captain in Her Majesty's Bengal Cavalry, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by. Her
Letters Patent, bearing date the Third day of April, in the year of our
Lord One thousand eight hundred and seventy-two, in the thirty-fifth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the, said. Alfred Robert Davidson Mackenzie, Her special
licence that I, the said Alfred Robert Davidson Mackenzie, my exe-
cutors, administrators, and assigns, or such others as I, the said Alfred
Robert Davidson Mackenzie, 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 "AN IMPROVED CONSTRUCTION OF IRON STEAM
SHIPS FOR TRADING PURPOSES," upon the condition (amongst others) that..
I, the said Alfred Robert Davidson Mackenzie, my executors or ad-
.

page_text: ministrators, 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
D
ministrators, 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 Alfred Robert Davidson Mackenzie,
do hereby declare the nature of the 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 accompanying Drawings, and to the figures and letters
marked thereon, that is to say :-
My Invention has for its object an improved construction of iron
steam ships for trading purposes, which while it affords a large carrying
capacity in proportion to the dimensions and cost of the vessel, requires
a lessened propelling power and at the same time combines the maximum
strength of hull, greatest attainable degree of safety in bad weather,
with ease of motion, minimum of pitching, reduced liability of engines
to race, and freedom from accumulation of deck water.
For this purpose I construct the hull of the vessel of a closed or box-
like form, that is, with an iron deck forming a continuation of the iron
sides, the transverse section amidships being approximately rectangular,
terminating fore and aft in the usual stem and stern posts, the deck
being, however, made considerably narrower towards both ends than in'
vessels of the usual construction, while the stern overhangs the stern
post only sufficiently to protect the rudder and screw propeller or pro-
pellers, as the case may be. At each end of the vessel is formed a
closed air chamber, and the entire remaining capacity of the hull, with
the exception of the engine and boiler rooms and water ballast chambers,
is rendered available for stowage of merchandize, a raised iron.deck-
house being provided amidships for containing the cabins for officers,
crew, and passengers, for store and sail rooms, and for steering gear.
This deck-house has no side openings communicating with the cabins
and its other compartments from the main or iron deck except for lights,
access being gained thereto and to the engine and boiler rooms below it
through its upper deck.
.:

page_text: The deck of the hull is entirely without bulwarks, and when loaded
the vessel has a low freeboard, so that it offers comparatively little
obstruction to the waves, which are free to wash over it, the raised deck-
house affording at the same time perfect safety and comfort to the crew
and passengers.
Over the bow air chamber is provided a raised anchor deck, the
anchors being by preference worked from capstans or winches in or
adjoining the deck-house, from which the cables pass along to the bows
over the deck.
If desired, the ordinary cargo hatchways may be extended, and a
portion of the deck may be sunk sufficiently to contain the hauling
gear, such as winches and cranes, for loading and unloading the vessel,.
which extended hatches with sunken deck gear below are closed in with
water-tight covers as required.
With this construction of steam ships it is proposed to have the
necessary gangways, ladders, and railings for giving safe access to every
part as required.
As an additional element of safety this improved arrangement of
steam ship would facilitate the formation of extended buoyant air
chambers along the upper sides or the deck of the ship, or both if
required, and such chambers may be simple extensions of the ordinary
water ballast chambers.
Another advantage of this improved construction of steam ship would.
be that in consequence of the comparatively reduced bulk of the ends.
of the ship and their air-tight construction, together with their reduced
weights, great facilities would be afforded for so trimming the vessel as
to give ready access to the outer surface of the hull at either end when
afloat, and this alteration of trim can be effected by filling a water-tight
compartment or introducing weight at either end, as may be required.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 on Sheet I. of the accompanying. Drawings shews a side
elevation of my before-described improved construction of iron steam
ships; Fig. 2 on Sheet II. shews a longitudinal section of the hull and:
deck-house; Fig. 3 shews' a half general plan of the hull and deck-
house, and also a half sectional plan through the deck-house, raised-
hatchways, and end_air chambers; Fig. 4 shews a transverse section of

page_text: the hull at the stern; Fig. 5 shews a transverse section through hold
and deck-house amidships; Fig. 6 shews a transverse section through
the hold and hatchways; Fig. 7 shews a transverse section at the bows,
and Fig. 8 shews a transverse section through the hold and hatchways
of a modified construction of the hull for passenger vessels.
The hull A is constructed of a closed or box-like form with iron
deck A¹, forming a continuation of the iron sides. The transverse
section for the greater part of its length is approximately rectangular, as
shewn at Figures 5 and 6, while towards the stern and bows the hull
assumes the usual shape, as shewn at Figs. 4 and 7, terminating in the
ordinary stem and stern posts. At each end of the vessel are formed
closed air chambers B and C for imparting increased buoyancy thereto,
and thus reducing the pitching motion to a minimum. In addition to
these air chambers other air chambers may be advantageously formed
along the sides and deck of the vessel, as shewn at D, D, Fig. 8, being
extensions of the water ballast chamber E. This construction is more
particularly applicable to large passenger vessels. A raised iron deck-
house F is constructed amidships for containing the cabins of officers,
crew, and passengers, and for store and sail rooms. This deck-house is
accessible through hatchways G, G, in the upper deck, there being no
side openings communicating with the iron deck A' of the hull, but
access can be gained to the deck A¹ from the deck-house by means of
ladders or steps H on the ends of the deck-house, as indicated in
Fig. 1. The deck-house is lighted by means of skylights I, I, on the
upper deck and by side lights J, J. Upon the deck-house is fixed
the steering gear K, and below this are capstans L for working the
anchors, the chains of which pass along the deck to the bows as shewn;
M is a raised anchor deck enclosing a water-tight air space N which
may be formed into a distinct upper bow air chamber, or be simply
an extension and part of the bow air chamber C; B, B, is a raised
deck aft enclosing a water-tight air space P, which may be formed
into a distinct upper stern air chamber or be simply an extension
and part of the stern air chamber B. The engines, boilers, &c., are
situated beneath the deck-house as shewn, access being gained thereto
through hatchways O, O, in the latter. The entire remaining space
Q, Q, of the hull is available for stowage of merchandize. Access is
gained to these spaces through raised hatchways R, R, provided with
water-tight covers, beneath which are sunken decks or platforms for
the hauling gear S, S, for loading and unloading. The deck A' has no

page_text: bulwarks but iron railings T, T, and raised gangways U may be pro-
vided for the safety of the crew in passing along the deck. At Fig. 1
and Figs. 4 to 9 the vessel is shewn sunk to load water line. It will be
seen that in this position the vessel has a low freeboard, so that it offers
comparatively little obstruction to the waves, which are free to wash
over it, while the deck-house affords perfect safety to the crew and
passengers.
Having thus described the nature of my said Invention and in what
manner the same is to be performed, what I claim is,-
First. Constructing iron steam ships wherein the following features
are combined, a hull of a closed or box-like form, the transverse section
whereof amidships is approximately rectangular, an iron deck forming
a continuation of the iron sides and having no bulwarks, a closed air
chamber or chambers at each end of the hull in place of the usual
cabins and forecastle, and a raised deck-house amidships containing
the cabins for officers, crew, and passengers, substantially as herein
described.
Second. In combination with the construction of steam ships set
forth in the first claim, the provision of air chambers along the sides or
the deck or both the sides and the deck of the ship, substantially as
herein described.
In witness whereof, I, the said Alfred Robert Davidson Mackenzie,
have hereunto set my hand and seal, this Second day of October,
in the year of our Lord One thousand eight hundred and seventy-
turn
ALFRED R. D. MACKENZIE. (L.S.)
ALFRED R. D. MACKENZIE. (L.S.)