IMPROVEMENTS IN THE CONSTRUCTION OF PROPELLERS, AND IN THE ARRANGE- MENT OF THE ENGINES AND DRIVING GEAR FOR ACTUATING the same
Year: 1874

page_text: LETTERS PATENT to Nicholas Demetrius Spartali, of Liverpool, in
the County of Lancaster, Steam Ship Agent, for the Invention of
"IMPROVEMENTS IN THE CONSTRUCTION OF PROPELLERS, AND IN THE ARRANGE-
MENT OF THE ENGINES AND DRIVING GEAR FOR ACTUATING the same,
"
Sealed the 23rd February 1875, and dated the 24th August 1874.
PROVISIONAL SPECIFICATION left by the said Nicholas Demetrius
Spartali at the Office of the Commissioners of Patents, with his
Petition, on the 24th August 1874.
I, NICHOLAS DEMETRIUS SPARTALI, of Liverpool, in the County of
Lancaster, Steam Ship Agent, do hereby declaro the nature of the said
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF PROPELLERS, AND IN THE
ARRANGEMENT OF THE ENGINES AND DRIVING GEAR FOR ACTUATING THE SAME," to
be as follows:-
In the ordinary propellers now in use in steam ships of large size and
beam the propelling surface of the blades (owing to the large size of the
boss at the central portion of the propeller) does not act usefully on the

page_text: centre water. The force of the curved sides of the blades is spent at a
distance round the said boss, and is carried round in a long circle. By
the blades being comparatively narrow and long, and having to sweep
through a large mass of water, the resistance to the blades and the
lifting of the water owing to the insufficiency of the angle from the
Íower to the upper portion of the circle is very considerable, and the
result is a waste of power and the causing of a centrifugal action and
thrusting of a great portion of the water on each side of the propeller
blades, leaving a great void in the centre.
By making the propeller blades of a large width, and by so diminishing
the area of the water to be displaced, and also by placing the blades in
two different vertical planes, one pair a little to the back and higher than
the other, and by angling the blades and making them thinner at the
base, while they are rapidly widened upwards from the shaft, the rotation
of the propelling blades takes place on a smaller centre, but at the most
useful and effective part; and by the manner they are placed in the two
different vertical inclined planes, and by the angular diagonal connection
of each two blades, they follow in quick succession one after the other,
and the one behind catching the water displaced by the former and part
of the fresh water in its immediate vicinity and at the back of the other,
thus causing the water continually displaced to coil in a great mass right
in the centre, and causing a strong reacting current behind the ship,
thereby considerably reducing the slip and the back water which is
caused by the ship's progress, and consequently increasing the speed. In
fact this propeller acts somewhat in the form of a concentric wheel, each
blade following close upon the other and presenting their greatest angle
or surface in their forward movement and for two-thirds or three-fourths
of the periphery traversed, and rising on their return in their smallest
angle, thereby reducing the lifting of the water to its very minimum.
By this arrangement I obtain all the useful work from the propeller and
no resistance to the rising of the blades, which enables me to work
propellers having larger surface and more blades and greater pitch than
heretofore, so that I obtain considerably more propelling power with the
same expenditure of motive power, and if more motive power be used a
considerably greater speed will be the result than is at present obtained
by the best propellers now in usc. I calculate from the experiments
made that tho gain in speed or engine power now used is about 25 to 30
per cent. from the causes above described.

page_text: In order to provide a clear run for or delivery of the water at the
central part of the propeller a curved diagonal channel is made in the.
boss between the blades by causing the curves on each side of the
blades to merge into the curves of the elliptical boss. The blades are
made wider at the upper part than at that part where they join the boss,
and at this part their hinder edges are cut away so as to allow a free-
deliverance of the water which would otherwise interfere with the proper
action of the forward and advancing edges of the blades. Propellers of.
this construction may be cast with the boss in one piece in the ordinary.
manner, or the boss may be cast with rudimentary blades, provided with
sockets, into which the remaining part of the blades may be fitted and.
secured in any convenient manner; or short arms may be forged or
fixed on to the shaft and the blades, or short or long rudimentary blades-
may be secured thereto in any convenient manner.
Sometimes (of course maintaining the blades in the manner and on
the angles described) I divide the boss into two distinct sections placed
diagonally or on a diagonal incline, one a little over the other, applied
to two different or on the same shaft in which I affix iron pegs and
double sheets of iron, forming a sheathing for sockets for the blades,
thus forming a strong and solid foundation. These sockets will form
part of the blades.
My improved propeller is admirably adapted for propelling on canals
or narrow channels from the fact of its curvilinear action and the
avoiding all side splash, which is so injurious to canal banking, and for
this purpose I make my propeller with two blades shorter than the other
two, the two longer blades carrying the displaced water all on one side
to the centre.
I prefer to use my improved propeller as a stern propeller, and to
place the same as far forward under the stern as can possibly be done,
instead of contiguous to the rudder or stern. post, as is now the caso;
but if desired a pair of them may be used as side propellers in place of
ordinary paddle wheels.
When my improved propellers are to be used as twin propellers I
place them both as near to the centre line of the ship as practically can be.
done, and not one on each side of the stern post as is now usually.
practised.

page_text: In constructing the propeller the one blade is fitted into its base
diagonally to the inclined planed base of the other, and cach pair
of blades presents the form of a pair of wings of large dimensions
placed diagonally on the shaft on two different centres. The one
centre or base is a little higher and abaft of the other, the four-
bladed propeller forming two pairs of wings, one placed a little higher
and abaft of the other. By this arrangement of the blades and centres
a compact concentrated wheel action is obtained, each blade falling
in the immediate wake the other in rapid succession, the one behind
covering the spot left by the previous one, and carrying forward the
water displaced by the former with additional overlapping surface
obtained in each successive blade by the effect of the angles of the
blades and the overlapping projection of the hinder edges of cach
successive blade. By this arrangement of the blades and centres tho
propelling action and scope of each blade begins in a line of a few
degrees beyond a line drawn horizontally from or diametrically through
the centre of the shaft, gradually developing its surface more and moro
to the water, and attaining its fullest broadest side when reaching the
point of a similar line drawn diagonally across the said centre, say,
about half way between that line and the aforesaid horizontal diametrical
line across the centre aforesaid, and to the extreme back of it. From
that point a large bulk of displaced water is carried downwards to the back
of the central vertical line of the centre of the shaft forming the circle.
Thus each blade is performing useful propelling work for about three-
fourths of the complete revolution round the axis of the shaft, and the
rising of the blade on that part of its revolution upwards takes place
at its minimum resistance to the water, the water having very little
hold on that maximum point of the slope of the blade, and returning
to the same starting point to repeat the same operation on each suc-
ceeding revolution.
.
The maximum displacement takes place between the extreme diagonal
point of the line from the axis, and the minimum from the opposite
angle of the same line to the above point which forms three-fourths of
the circle. The remaining travel of the blade presents its greatest slope
on its rise to the starting point of propulsion, and thus reduces the
resistance to the water to its minimum. By this arrangement of
diminished resistance to the blades by the water I am able to increase
the pitch of my blades without increase of engine power.

page_text: I adopt a somewhat similar modified bladed propeller and diagonal
wheel and blades to work on the sides of a vessel in substitution of the
present paddle wheels, substituting for the horizontal floats the improved
angled curved sloping floats or blades, presenting their greatest surface
to the water on their forward movement, and returning to the upper
surface at their maximum slope and least resistance, all within a con--
centrated compact circle. The number of floats will be diminished;
in proportion to the diameter and diagonal planes of the blades having
the same or a smaller centre and framework.
I
propose sometimes to place one of my improved propellers at the
bows, and another at the stern of a screw ship, and by this arrangement.
the driving power required for driving the stern propeller will be much
reduced.
My next improvement relates to an improved construction of engine
suitable for driving my improved propellers. Instead of having a long
driving shaft with numerous bearings I have a short shaft, and I
counterbalance the weight of the propeller outside the ship by adapting
to the shaft a cylindrical weight which will act as a fly wheel. This
weighted shaft is driven by means of a crank and connecting rod, the
upper end of which is keyed to a series of discs which are driven by a
vibrating or other suitable engine or engines. The shaft on which the
discs are mounted extends to the stern, and by means of a crank and
connecting rod placed inside the box which forms the stern post the
upper or countershaft is connected with the outer end of the propeller
shaft, and assists in driving the same by the same or by an additional
engine, and either connected to or independent of the other shaft and
gearing. Or I communicate motion from the motive-power engine to
the running shafts by means of an universal joint.
I would remark that for large vessels I may make my propellers
with five, six, or more blades, all placed in the same manner as above
described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Nicholas Demetrius Spartali in the Great Seal
Patent Office on the 24th February 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, NICHOLAS
DEMETRIUS SPARTALI, of Liverpool, in the County of Lancaster, Steam
Ship Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of August, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Nicholas Demetrius Spartali, Her
special licence, that I, the said Nicholas Demetrius Spartali, my exe-
cutors, administrators, and assigns, or such others as I, the said
Nicholas Demetrius Spartali, for 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 “IMPROVEMENTS IN PROPELLERS, AND IN THE
ARRANGEMENT OF THE ENGINES And Driving Gear FOR ACTUATING THE SAME,"
upon the condition (amongst others) that I, the said Nicholas Demetrius
Spartali, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and scals, should par-
ticularly 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 Scal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Nicholas Demetrius Spartali, 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, reference being had to the
Drawing hereunto annexed and to the letters and figures marked thercon
(that is to say) :-
In the ordinary propellers now in use in steam ships of large size and
beam the propelling surface of the blades (owing to the large size of the

page_text: boss at the central portion of the propeller) does not act usefully on the
centre water. The force of the curved sides of the blades is spent at a
distance round the said boss, and is carried round in a long circle. By
the blades being comparatively narrow and long, and having to sweep
through a large mass of water, the resistance to the blades and the
lifting of the water owing to the insufficiency of the angle from the
lower to the upper portion of the circle is very considerable, and the
result is a waste of power and the causing of a centrifugal action and
thrusting of a great portion of the water on each side of the propeller
blades, leaving a great void in the centre.
By making the propeller blades of a large width, and by so diminishing
the area of the water to be displaced, and also by placing the blades in
two different vertical planes, one pair a little to the back and higher than
the other, and by angling the blades and making them thinner at the
base, while they are rapidly widened upwards from the shaft, the
rotation of the propelling blades takes place on a smaller centre but at
the most useful and effective part. Moreover, by the manner they are
placed in the two different vertical inclined planes and by the angular
diagonal connection of each two blades they follow in quick succession
one after the other, and the one behind catching the water displaced by
the former and part of the fresh water in its immediate vicinity and at
the back of the other, thus causing the water continually displaced to
coil in a great mass right in the centre, and causing a strong reacting
current behind the ship, thereby considerably reducing the slip and the
back water which is caused by the ship's progress, and consequently
increasing the speed. In fact, this improved propeller acts somewhat in
the form of a concentric wheel, each blade following close upon the
other and presenting their greatest angle or surface in their forward
movement, and for two-thirds or three-fourths of the periphery traversed,
and rising on their return in their smallest angle, thereby reducing the
lifting of the water to its very minimum. By this arrangement I obtain
all the useful work from the propeller and no resistance to the rising of
the blades, which enables me to work propellers having larger surface.
and more blades and greater pitch than heretofore, so that I obtain con-
siderably more propelling power with the same expenditure of motive
power, and if more motive power be used a considerably greater speed
will be the result than is at present obtained by the best propellers now
in use. I calculate. from the experiments made that the gain in speed

page_text: on engine power now used is about twenty-five to thirty per cent. from
the causes above described.
In order to provide a clear run for or delivery of the water at the
central part of the propeller a curved diagonal channel is made in the
boss between the blades by causing the curves on each side of the blades
to merge into the curves of the elliptical boss. The blades are in some
forms of propeller made wider at the upper part than at that part where
they join the boss, and at this part their hinder edges are cut away so as
to allow a free deliverance of the water, which would otherwise interfere
with the proper action of the forward and projecting advancing edges of
the blades. Propellers of this construction may be cast with the boss in
one piece in the ordinary_manner, or the boss may be cast with rudimen-
tary blades provided with sockets, into which the remaining part of the
blades may be fitted and secured in any convenient manner. Or short
arms may be forged or fixed into the shaft, and the blades or short or long
rudimentary blades may be secured thereto in any convenient manner.
Sometimes (of course maintaining the blades in the manner and on
the angles described) I divide the boss into two distinct sections placed
diagonally or on a diagonal incline one a little over the other applied to
two different or on the same shaft in which I affix iron pegs and double
sheets of iron forming a sheathing for sockets for the blades, thus forming
a strong and solid foundation. These sockets will form part of the
blades.
My improved propeller is admirably adapted for propelling on canals
or narrow channels from the fact of its curvilinear action and the
avoiding all side splash which is so injurious to canal banking, and for this
purpose I make my propeller with two of the blades shorter than
the other two, the two longer blades carrying the displaced water
all on one side to the centre.
I prefer to use my improved propeller as a stern propeller and to
place the same as far forward under the stern as can possibly be done,
instead of contiguous to the rudder or stern post as is now the case, but
if desired a pair of them may be used as side propellers in place of
ordinary paddle wheels.
When my improved propellers are to be used as twin propellers, I
place them both as near to the centre line of the ship as practically can

page_text: De done, and not one on each side of the stern post, as is now usuany
practiced.
other.
In constructing the propeller the one blade is fitted into its base
diagonally to the inclined planed base of the other, and each pair of
blades presents the form of a pair of wings of large dimensions placed
diagonally on the shaft on two different centres; the one centre or base
is a little higher and abaft of the other. The four-bladed propeller
forming two pairs of wings, one placed a little higher and abaft of the
By this arrangement of the blades and centres a compact,
concentrated wheel action is obtained, each blade falling in the
immediate wake of the other in rapid succession, the one behind covering
the spot left by the previous one and carrying forward the water
displaced by the former with additional overlapping surface obtained in
each successive blade by the effect of the angles of the blades, and the
overlapping projection of the hinder edges of cach successive blade.
By this arrangement of the blades and centres the propelling action and
scope of each blade begins in a line of a few degrees beyond a line drawn
horizontally from or diametrically through the centre of the shaft
gradually developing its surface more and more to the water, and
attaining its fullest broadest side when reaching the point of a similar
line drawn diagonally across the said centre, say about half-way between
that line and the aforesaid horizontal diametrical line across the centre"
aforesaid, and to the extreme back of it. From that point a large bulk
of displaced water is carried downwards to the back of the central
vertical line of the centre of the shaft forming the circle. Thus each
blade is performing useful propelling work for about three-fourths of thie'
complete revolution round the axis of the shaft, and the rising of the
blade on that part of its revolution upwards takes place at its minimum
resistance to the water, the water having very little hold on that
maximum point of the slope of the blade and returning to the same'
starting point of driving the water forward to the other side, in order to
repeat the same operation on each succeeding revolution.
.
The maximum displacement takes place between the extreme diagonal
point of the line from the axis, and the minimum from the opposite.
angle of the same line to the above point which forms three-fourths of the.
circle. The remaining travel of the blade presents its greatest slope on.
; its rise to the starting point of propulsion, and thus reduces the resistance:
to the water to its minimum. By this arrangement of diminished

page_text: resistance by the water to the blades I am able to increase the pitch of
my blades without necessarily increasing the engine power.
I adopt a somewhat similar modified bladed propeller and diagonal
wheel and blades to work on the sides of a vessel in substitution of the
present paddle wheels, substituting for the horizontal floats the improved
angled curved sloping floats or blades, presenting their greatest surface
to the water on their forward movement and returning to the upper
surface at their maximum slope and least resistance, all within a con-
centrated compact circle. The number of floats will be diminished in
proportion to the diameter and diagonal planes of the blades, having the
same or a smaller centre and framework.
I sometimes place one of my improved propellers at the bows and
another at the stern of a screw ship, and by this arrangement the driving
power required for driving the stern propeller will be much reduced.
The principle of my propeller lies in the fixing or joining of two long
square planes of wood or metal at their angles vertically (and shaped
into blades) corner to corner and diagonally one blade to the other with
the shaft passing through the centre from the back of the two blades,
and for a four-bladed propeller two similar pairs of blades are placed in
a similar angle to the base of the other two, each pair forming the a
distinct pair of wings above mentioned, the one working diagonally
above and at the back of the lower pair. The four blades are cast with
one boss at the back of their ends of all, thus forming one solid casting;
or a boss angled to the shape of the base of the blades may be made with
wrought-iron sockets or arms, into which the blades can be fitted, bolted, a
rivetted, or otherwise secured. Each of the two blades thus fitted
together works as if a semicircular blade of sheet iron was bent in the
centre in the form of a diagonal letter f, as shewn in side and end views
at Figure 1 of the Drawing. This double blade is fitted into a shaft
and works around its diagonal centre.
g
It will be seen that the blades being curved towards the back of the
centre, they reach a much greater point to the back of the boss from the
hind upper part of the water at the ship's stern, and displace a much
larger volume of water from that point to the other side or under part of
the diagonal point of the blades to the immediate front of the boss, and 3
by this peculiar angling of the blades and centre the rubbing surface to

page_text: the water is reduced to a minimum, the work of displacement being done
chiefly by the angles and the gentle and graduated travel of the blades
more than by the surface, as is the case more or less with the present
propellers in use.
At Figure 2 I have shewn two side perspective views of a two-bladed
propeller which is a modification of Figure 1. In this instance the two
halves of the propeller are set on the boss at an angle to each other
though revolving in a circle. By this peculiar mode of angling and
fixing the blades and centres and elongating the reach of the extreme
points of the blades diagonally from the centre the action of the pro-
peller is much like that of oars as worked in rowing boats.
Another advantage lies in the utilizing the whole of the centre of the
propeller and returning the blades to the starting point of propulsion at
their extreme angles with scarcely any perceptible resistance to the
water, and no lifting, or splashing, or carrying the water round, or
causing centrifugal action between the blades.
Figure 3 represents side and end views of a propeller constructed
with four blades, on the principle shewn at Figure 1; and Figures 4, 4ª,
4%, and 4 are front or end, side, back, and perspective views of a four-
bladed propeller, constructed according to the plan shewn at Figure 2.
When higher speed or a larger propelling-surface.is.required I.employ
a multi-bladed propeller fitted into a long triangular or quadrangular
edged boss gradually tapering into a cone shape, as shewn in end and
side views at Figure 5. Or the boss may be made cylindrical and the
blades fixed at angles into sockets or on pegs and arranged in a similar
curved diagonal course or angle in relation of one to the other, as shewn
at side and end views at Figure 6.
It will be seen that the one blade falls partly in the water and partly
overlaps the other in rapid succession, and by the difference of the
gradual inclined boss and the angles forming the sockets of the blades
the circle described by each blade and by each set of graduated blades
consisting of two, three, or more blades in a row will differ from that of
the other of each blade and set of three, four, or more blades, as above.
:
It will moreover be seen that in Figure 5 I have arranged diagonally
behind or between the sets of long blades additional sets of shorter

page_text: blades which will receive the water from the long blades, and will con-
sequently increase the power of the propeller.
At Figure 7 I have shewn a modification of my multi-bladed propeller,
the difference in construction consisting mainly of cranked arms or
pegs, into which are fixed the diagonal blades. By this means I gain a
still longer reach of blade forward, and at same time I obtain a greater
strength and a greater resisting power to the strain and against the
power of the water.
I construct paddle wheels or side propellers on the same principle as
the stern screw, as mentioned in the introductory part of my Speci-
fication, that is, the blades or floats are set diagonally on the shaft in
pegs or arms arranged diagonally round the shaft. Figure 8 is an end
view and Figure 8* a side view of a side propeller constructed in this
manner, and shews a series of blades set on or graduated round and
elongated round or triangular or quadrangular boss. The pegs forming
the roots, stalks, or sockets of the blades of side wheel propellers may
be cranked, as above described and shewn at Figure 7, the one blado
falling in rapid succession to the back and side of the other, and one set
of two or three blades or floats similarly in succession to the other.
Figure 10 is a side view of a paddle wheel constructed with cranked
floats in the manner just described. It will be seen therefore that a framed
wheel to act as a paddle wheel may be constructed on the principle
shewn at Figure 7, the floats or blades being placed diagonally across
the width in graduated diagonal sets of cranked arms or pegs. The full
face or surface of the blades or floats is developed diagonally from the
centre of their extreme forward reach close to the vessel's sides, thereby.
thrusting the water to the extreme back diagonally, such blade or float
returning back in its revolution upwards at its extreme curved angle,
thus rising through the water at its least angle of resistance, and thus
doing away with all backwater lifting, as is the case with all paddle
wheels in use, more or less. By this improved arrangement a saving of
from forty to fifty per cent. of the propelling power is effected and a
considerable increase of speed is obtained.
Figures 11, 11, and 11 are various views of a stern propeller in
which the propeller blades, four in number, are made of a large width,
as mentioned in the introductory part of my Specification, and by so

page_text: diminishing the area of the water to be displaced and also by placing
the two pairs of blades in two different vertical planes, one pair a little
at the back and higher than the other, and by angling the blades and
making them thinner at the base while they are rapidly widened
upwards from the shaft the rotation of the propelling blades takes place
on a smaller centre, but at the most useful and effective part. These
blades are arranged in pairs, and in order that their construction may be
more clearly seen and understood the two pairs are shewn detached at
Figures 11 and 11ª.
Figures 12, 12ª, 12, and 12º, represent various views of a four-bladed
propeller, which is a modification of the above. In this instance the
four propellers are in one piece with the boss, and in order to provide a
clear run for or delivery of the water at the central part of the propeller
a curved diagonal channel is made in the boss between the blades by
causing the curves on cach side of the blades to merge into the curves
of the elliptical boss.
My next improvement relates to an improved construction of engine
and arrangement of gear suitable for driving my improved propellers.
This improvement is shewn in the accompanying Drawings at Figuro 13,
which is a sectional clevation of the stern part of a ship with my
improvements adapted thereto. Instead of having a long driving shaft
with numerous bearings I have a short shaft, and I counterbalance the.
weight of the propeller outside the ship by adapting to the driving shaft
a cylindrical weight a, which will act as a fly wheel. This weighted
shaft is driven by a pair of engines by means of cranks and connecting.
rods which actuate a shaft connected to the propeller shaft by means of
a disc or discs b. The propeller shaft on which one of the discs is
mounted extends to the stern, and by means of a crank c and connecting
rod d placed inside the box which forms the stern post the upper or
countershaft e is connected with the outer end of the propeller shaft,
and assists in driving the same by means of an additional engine, which
may be either connected to or independent of the other shaft and
gearing, or I communicate motion from the motive-power engine to
the running shafts by means of an universal joint instead of the discs.
I find it desirable to construct and arrange the valves for the supply
and exit of the steam in the manner shewn at Figure 14, which repre-
sents a vertical section of an engine cylinder constructed in the improved

page_text: I further claim the improved construction of valve box, and slide
alve, and steam passage arrangements, as shewn.
In witness whereof, I, the said Nicholas Demetrius Spartali, have
hereunto set my hand and scal, the Twenty-third day of February,
in the year of our Lord One thousand eight hundred and
seventy-five.