PROPELLING VESSELS OR BOATS THROUGH THE WATER ON A NEW PRINCIPLE AND METHOD, AND BY A NEW APPLICATION OF MACHINERY
Year: 1875

page_text: LETTERS PATENT to Henry Robert Lumley, of 14, Marlborough
Place, Saint John's Wood, London, for the Invention of " PROPELLING
VESSELS OR BOATS THROUGH THE WATER ON A NEW PRINCIPLE AND METHOD,
AND BY A NEW APPLICATION OF MACHINERY."
Scaled the 10th March 1876, and dated the 19th October 1875.
PROVISIONAL SPECIFICATION left by the said Henry Robert
Lumley at the Office of the Commissioners of Patents, with his
Petition, on the 19th October 1875.
I, HENRY ROBERT LUMLEY, of 14, Marlborough Place, Saint John's
Wood, London, do hereby declare the nature of the said Invention for
"PROPELLING VESSELS OR BOATS THROUGH THE WATER ON A NEW PRINCIPLE AND
METHOD, AND BY A NEW APPLICATION OF MACHINERY," to be as follows:-
I designate my Invention "the screw clad," and its object is to
propel vessels or boats of any description through the water, not
applying the screw propeller in the manner now and heretofore
customary, but attaching the screw or screws to each side of the

page_text: vessel at its bottom, as near to each side of the keel as desirable; the
row or rows of screws on each side of the vessel to extend the whole
length of its bottom, or to any length between the stem and stern that
may be wished, using as many rows of screws between the keel and the
waterline as desired. The screws are to receive their rotary action
from mechanical power within the vessel as underneath described.
The shaft or spindles of the screw rotate in two ends of bars, which
bars are brought round by the side of the screw and fastened to the
ship's side opposite the centre of the screw. The driving shaft or shafts
work a large wheel or wheels at the exterior of the ship; these com-
municate rotary motion to a rod or rods, the ends of which are connected
by small cog wheels to cog wheels at the ends of the shafts or spindle.
The advantages gained are the very rapid rotary action of the screw,
which thus prevents to a great extent the "slip" or loss of the screw's
power, and gives greater speed to the vessel; such rapid rotary motion
could not be used direct from within the vessel as the speed of the
rotation would cause serious friction and the heating of the bearings of
the screw shaft.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Robert Lumley in the Great Seal
Patent Office on the 13th April 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
ROBERT LUMLEY, of 14, Marlborough Place, Saint John's Wood, London,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of October, in the
year of our Lord One thousand eight hundred and seventy-five, in tho
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Henry Robert Lumley, Her
special licence, that I, the said Henry Robert Lumley, my executors,
administrators, and assigns, or such others as I, the said Henry
Robert Lumley, 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

page_text: 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 "PROPELLING VESSELS OR BOATS THROUGH THE WATER ON A NEW
PRINCIPLE AND METHOD, AND BY A NEW APPLICATION OF MACHINERY," upon the
condition (amongst others) that I, the said Henry Robert Lumley, my
executors or administrators, 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 Henry Robert Lumley, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement :-
My Invention consists of a new method of propelling vessels through
water upon a principle which I call the "screw clad," by which term I
designate a series of screw propellers, the screws or propellers being
placed in a particular position, and being driven by a special adaptation
of machinery at the exterior of the vessel. I attach screws to each sido
of the vessel as near to each side of the keel as I may find most
desirable, placing the row or rows of screws always on the exterior fore
part of the vessel, that is to say, in front of the centre of the vessel.
By means of ordinary driving shafts or connections inside the ship,
working wheels and mechanism at the exterior of the ship, I give rapid
rotary motion to the spindles of the screws or propellers.
On the accompanying Sheet of Drawings Figure 1 represents a side
view of a ship embodying my Invention, Figure 2 being a plan of the
same, and Figure 3 a midship section thereof drawn to an enlarged scale,
and shewing driving gear within the ship, similar letters of reference
denoting similar parts in each of the Figures respectively.
A, A, A, are the screws; B, B, B, brackets or supports for carrying
the same.
CCC ninions secured on to ends of screw shafts a. a. a.

page_text: a, a, a, screw shafts working in bearings b, b, b, in brackets B, B, B.
F, F, F, guards attached to the ship to protect screws.
G, G¹, G, wheels secured on to inner ends of shafts E communicating
motion from one to another, and so arranged that the wheels G¹, G",
may be drawn out of gear when only one screw is required to be
driven.
The shafts E, E, E, in the interior of the ship receive their rotary
action from the steam engine in the ordinary way, and communicate
rotary action to the large driving wheels D, D, D, which are at the
exterior of the vessel. The pinions C, C, C, convey the rapid motion
communicated to them to the spindles or screw shafts a, a, a, of the
screws A, A, A, which drive the ship.
By the arrangement of two or more screws or propellers on each side
of the vessel in front of the centre the vessel instead of presenting a
smooth surface wherewith to cut through a smooth body of water
presents a nearly entirely moving surface to the smooth body of the
water, thus preventing adhesion. Hereby the "screw clad" uses its
surface to cleave as well as propel; and I further obtain the advantage
of propelling through the vacuum obtained forward of the screws by
their very rapid rotary motion.
By applying the "
screw clad"
screws or propellers to the fore part of
the vessel, beyond its centre, an angular direction of the screws or
propellers is obtained, that is, an angular direction to that straight
line which could be drawn between the stem and the middle of the stern
of a vessel. By this angular direction of the screws of propellers a
complete power is obtained over the head of the vessel.
C
The great disadvantage the steam vessel has hitherto been at in
comparison with the sailing vessel is this deficiency of direct power
over the head of the vessel, but under the arrangement of the angular
direction of the screws or propellers in my screw clad" system the
head of the vessel can be kept up to any sea and hove to closely in a
gale of wind. The direction of the power, which I call "line of force,"
that my screws take follows the sides of the vessel on cach side to the
stem, and as it were takes hold of the head and keeps it in powerful

page_text: "
command, which would not be the case were the screws placed behind
the centre or at the centre. In the case of paddles or screws amidships
the head of the vessel is not under the like control as the "lines of
force are parallel to the centre and parallel to the stem of the vessel.
In the case where the screws are placed at the stern of the vessel the
"line of force" though going direct to the stem is too distant from its
origin to be a direct powerful force and one sufficient to contend against
the action of a stress of weather on the stem; while my screw clad" is
a direct application of the whole force of the screws or propellers on the
fore part of the vessel and on the stem.
ઃઃ
Further, by the contiguity of one row of screws to the keel while the
upper row or rows will also be considerably below the water line I
ensure the uninterrupted power of the screws upon the water during all
weather, but should the upper row or rows of screws be even exposed
for a moment by the roll of the waves or pitch of the vessel the lower
screws will always be submerged and in constant action, both to propel
the vessel and to keep the head under command; and in case of accident
to any one screw or row of screws the vessel will not be deprived of the
use of her steam power, as in the case of accident to a screw or screws at
the stern or accident to a screw where a screw is placed amidship on each
side of the vessel. The screw at the stern of a vessel in rough weather
often works out of the water during the roll of the waves and the pitch
of the vessel, and full command over the vessel is lost for so long; this
can never be the case with my screw clad," for the lower screws being
always submerged the head of the vessel will always be under command,
and the vessel be propelled by the screws, while the driving machinery
inside the vessel can be disconnected from a disabled screw or screws
and applied solely to drive those not disabled, or which it may be
desired to drive. Likewise there will be a total absence of the danger
to which a screw placed at the stern is liable; also full protection of the
lower screws from gun shots.
66
By the considerable length of screw which the position of the screws
enables me to obtain I develope the screw principle under its most
advantageous condition, namely, that of length, and thereby I overcome
the loss of power by "slip."
By the use of a long screw I am enabled to narrow the diameter of

page_text: a nearer leverage to the "line of force" which the screw spindlo has
derived from the mechanical action upon it.
"
By the application of my screw clad" principle to the fore part of
the vessel I obtain in comparison with the application of a screw or
screws astern or of paddles or screws at the centre of a vessel the great
advantage of a pulling power over that of a pushing power.
By employing an exterior mechanical action to work my screw
clad" screws or propellers greater speed of rotation of the screw is
obtained, and the action of the large exterior cogged wheels which
receive motion from the machinery inside the vessel is on the whole,
and solely as far as these cogged wheels are concerned, favorable to
propulsion, as one part of the rotary action of these large exterior
cogged wheels more than neutralizes any reverse tendency of the other
part of their rotary action. On the other hand the great speed of the
screw obtained by this principle tends to entirely overcome the "slip"
of the screw or propeller.
Further, by my manner of applying power to drive the screws or
propellers the whole power of the steam engine is applied through the
screw or propeller to the bars or staunchions that are fastened to the ship,
and in which the screw rotates, and the bars or staunchions receive the
forward pressure of the screw or backward pressure when required,
contrary to the case of the stern screws or to paddle wheels, which pass
and return a portion of their force adversely into the steam engine
machinery which has given them action.
Having now described and ascertained the nature of my said Inven-
tion and in what manner the same is or may be performed, I would have
it understood that I do not limit myself to any particular dimensions of
parts in their relation to each other, to the use of any particular driving
gear within the ship for driving the exterior toothed gearing, or to the
accessory parts, as illustrated on the accompanying Sheet of Drawings,
as such fittings may be varied without departing from the principle of
my Invention, which is that by the number of screws employed, by
their position, by their exceptional length and the rapidity of their
rotary action, by their pulling power, by the command of the head of
the vessel, by the constant action of the screws I obtain a vastly
increased rate of speed and greater safety of the vessel; finally, I claim
as secured to me by the herein-before in part recited Letters Patent,―

page_text: Firstly. The propulsion of vessels or boats through the water by means
of screws placed on each side forward of the centre of the vessel.
Secondly. In order to drive the screws thus placed the use of
toothed gearing placed outside the vessel, and in preference the
adaptation of this exterior principle, substantially as herein-before
set forth and shewn on the accompanying Drawing.
In witness whereof, I, the said Henry Robert Lumley, have
hereunto set my hand and seal, this Tenth day of April, in
the year of our Lord One thousand eight hundred and seventy-
six.