IMPROVEMENTS IN STEAM ENGINES, AND IN PROPELLING VESSELS
Year: 1849

page_text: rn the latter of a Patent granted to ROBERT GRIFFITHS, of Havre,
Engineer, for the Invention of "IMPROVEMENTS IN STEAM ENGINES, AND
IN PROPELLING VESSELS," bearing date at Westminster, the Thirteenth
day of September, One thousand eight hundred and forty-nine.
DISCLAIMER AND MEMORANDUM OF ALTERATION proposed to be
entered by the said Robert Griffiths with the Clerk of the Patents of
England, pursuant to the Statutes in that case made and provided.
WHEREAS, in the Specification of the said Patent, the Invention was
described to consist of improvements in steam engines, and also of improve-
ments in propelling vessels, and as those parts of the Invention which relate
to steam engines, and also that part of the improvements in propelling vessels
which consists in a self-regulating pitch of the propeller to the power of the
engine, have not come into use; I therefore wish to disclaim, and I do hereby
disclaim, all those parts of the said Specification, and also of the title of the said
Invention, which describe and claim improvements in steam engines, and in
the self-regulating pitch of the propeller to the power of the engine; and I
alter the said Specification by introducing the words, but no claim is made to
inclining blades of screw propellers, or to their being made open in the centre
at the end of the paragraph, which is in the following words: "Figures 6
"and 7 represent an end and longitudinal elevation of a propeller having four
"blades, two being inclined forwards, the other two backwards," and I strike
out the words, "Fifth, I claim;" also the words, "Sixth, in;" and also the
words, "Lastly, I claim," near the end of the said Specification, and I intro-
duce the word also after the word "bosses" at the end of what will be the
.

page_text: first claiming clause of the said Specification after such alterations have been
made as aforesaid.
And in order that the effect of this Disclaimer and Memorandum of Alter-
ation may be better understood, I annex a copy of the Specification as it will
appear when such Disclaimer and Alterations have been made..
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"TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
GRIFFITHS, of Havre, Engineer, send greeting.
"WHEREAS Her present most Excellent Majesty Queen Victoria, by
"Her Royal Letters Patent, under the Great Seal of the United Kingdom
"of Great Britain and Ireland, bearing date at Westminster, the Thirteenth
day of September One thousand eight hundred and forty-nine, in the thir-
"teenth year of Her reign, did, for Herself, Her heirs and successors, give
" and grant unto me, the said Robert Griffiths, my exors, adññors, and
assigns, Her especial license, full power, sole privilege and authority, that I,
the said Robert Griffiths, my exors, admors, and assigns, and such others as
I, the said Robert Griffiths, my exors, adñors, or assigns, should at any
time agree with, and no others, from time to time and at all times during
the term of years therein expressed, should and lawfully might make, use,
"exercise, and vend, within England, Wales, and the Town of Berwick-upon-
"Tweed, my Invention of "IMPROVEMENTS IN PROPELLING VESSELS;" in which
*" said Letters Patent is contained a proviso, that I, the said Robert Griffiths,
"should cause a particular description of the nature of my said Invention,
"and in what manuer the same is to be performed, by an instrument in
writing under my hand and seal, to be inrolled in Her said Majesty's High
Court of Chancery within six calendar months next and immediately after
the date of the said in part recited Letters Patent, as in and by the same,
"reference being thereunto had, will more fully and at large appear..
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"NOW KNOW YE, that in compliance with the said proviso, I, the said
"Robert Griffiths, do hereby declare that the nature of my said Invention,
" and the manner in which the same is to be performed, are fully described
and ascertained in and by the following statement thereof, reference being
"had to the Drawings hereunto annexed, and to the figures and letters marked
thereon, that is to say:-"
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"The nature of my Invention consists in the construction of propellers for
vessels, as herein described, reference being had to the Drawings hereto
annexed, and to the letters marked thereon, similar letters of reference being
"used to denote similar parts in all the Drawings."
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$6
Drawing C, Figure 1, shews a side elevation, and Figures 2 and 3 longi-
tudinal and transverse sections, of my improved propeller, the centre of

page_text: "
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"which consists of a hollow metal sphere a, in which is placed the boss b,'
with sockets to receive the shanks of the blades c, c, secured therein by the
"lever arms d, d, having lateral play in the socket of the boss b. The outer
"ends of these arms act upon the sliding box e, which moves longitudinally
on the shaft against the collar g, held by the lever h, which is connected
to the governor spring k by the rod I, having an adjusting screw L. The
"action of this arrangement is as follows:-When the propeller is set to
"work the leading portion of the blades meet with greater resistance than the
"after part, according to the velocity it is driven, inducing the blades by the
"amount of this extra pressure upon their leading sides to increase the angle
or pitch forward, causing the lever ȧrms d to press forward the sliding box e;
"which rotates against the collar g; this sliding motion is controlled by the
spring K placed within the engine room or other suitable position, which is
regulated to the proper resistance by the adjusting screw L on the rod I.
Now, whenever the propeller meets with less resistance from favourable
"winds or currents, the speed of the engine increases, and the increased
"speed of the propeller throws a proportional increasing pressure on the
leaning side of the blades greater than the adjusted resistance of the
governor spring K, which is compressed by the rod I, forced forward by
"the sliding box e against the collar g, the pitch increases until the propeller
"throws a greater load on the engine, and reduces it down again the number
"of revolutions instantaneously with which the differential pressure between
"the leading and after portions of the blade is diminished, and the governor
"spring K forcing back the sliding bar e, adjusts the true pitch of the
propeller to the power and proper speed of the engines, which by this means
"have always their full effective power made available under all circum-
"stances of currents and winds. I am aware that it has been before proposed
"to alter the pitch of screw propellers when working; I do not, therefore,
"claim this as my Invention."
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"By the filling up of the centre portion of the propeller the prejudicial
centrifugal action upon the water, and consequent waste of power is avoided,
"and the propeller strengthened, and although I prefer the form of a sphere,
as shown in Drawing C,, the same may be accomplished in a conical, egg,
or other suitable form, or may be made either, as shewn, entirely on the
propeller shaft, or with a centre portion only attached to the propeller, the
"ends being fixtures to the dead wood and stern post. I do not confine myself
"to the precise method of filling up the centre of the propeller, so long as the
peculiar nature of this part of my Invention be retained."
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Figure 4 represents the blades C, C, of a propeller inclined forward

page_text: "towards the vessel'; this form I have found most suitable for full sterned
"ships."
"Figure 5 represents a propeller, the blades, of which are made open in 'the'
"centre."
Figures 6 and 7 represent an end and longitudinal elevation of a propeller
"having four blades, two being inclined forwards, the other two backwards,
" but no claim is made to inclining blades of screw propellers, or to their
being made open in the centre."
"Figures 8 and 9 represent two views of the ordinary form of propeller
"fitted with my improved centre, and Figure 10 my improved tapered blades
"with the ordinary boss."
"The blades c, c, of Figures 1, 2, 3, 4, 5, 6, and 7, are shewn, as in Figure 10,
tapered towards their outward extremities, which I find in practice to be'
"the best form; the same, however, may be varied, as well as the position of
"the shank C, which may be placed behind the centre of the blade when it
" is desirable to increase the pressure of the leading side against the governor
spring K, as described with respect to Figures 1, 2, and 3, in Drawing C.".
Having now described the nature of my Invention and the manner in
which the same is to be performed, I would have it understood that I do
"not confine myself to the precise details herein described, provided the
"peculiar character of either part of my Invention be retained; but what I'
"claim is the filling the centres of propellers as berein described in contra-
" distinction to and beyond what has been heretofore practised in forming
"their centres or bosses; also forming propellers as described in respect of
"Drawing C, Figures 4, 5, 6, and 7; and the making of propeller blades
narrower or tapered towards their outside extremities, in contradistinction to
"the form hitherto adopted of increasing the width of that part of the blade."
"
In witness whereof, I, the said Robert Griffiths, have hereunto set my
hand and seal, this Fifteenth day of December, in the year of our Lord
One thousand eight hundred and sixty.
This is to certify, that the above-named Robert Griffiths has applied to me
for leave to enter with you the above-written Disclaimer and Memorandum
of Alteration of part of the title and Specification of the above Invention, and
for which Letters Patent were granted to him under the Great Seal of Great
Britain, bearing date at Westminster the Thirteenth day of September, One

page_text: thousand eight hundred and forty-nine. And on considering the said applicà-
tion I directed the said Robert Griffiths, to advertise the same in the London
Gazette, and the Times, Morning Herald, and Birmingham Daily Post news-
papers, and which advertisements having been duly published in the said
London Gazette on the Sixteenth day of November, and in the Morning
Herald Newspaper on the Seventeenth day of November, ad the Times and
Birmingham Daily Post Newspapers on the Nineteenth day of November last,
and no objection having been made to the said application, I have accordingly
granted leave to the said Robert Griffiths to enter and file his said Disclaimer
and Memorandum of Alteration, pursuant to the Statutes in that case made
and provided.
AND BE IT REMEMBERED, that on the Fifteenth day of December,
in the year of our Lord 1860, the aforesaid Robert Griffiths came before
our said Lady the Queen in Her Chancery, and acknowledged the Disclaimer
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Disclaimer aforesaid was stamped according to
the tenor of the Statute made for that purpose.

page_text: DHALL
, 1, ROBERT
GRIFFITH, of Havre, Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of
Great Britain and Ireland, bearing date at Westminster, the Thirteenth
day of September, One thousand eight hundred and forty-nine, in the thir-
teenth year of Her reign, did for Herself, Her heirs and successors, give
and grant unto me, the said Robert Griffiths, my exors, adññiors, and assigns,
Her especial licence, full power, sole privilege and authority, that I, the said
Robert Griffith, my exors, adñiors, and assigns, and such others as I, the
said Robert Griffith my exors, adñiors, or assigns, should at any time agree
with, and no others, from time to time and at all times during the term of
years therein expressed, should and lawfully might make, use, exercise, and.
vend, within England, Wales, and the Town of Berwick-upon-Tweed, my
Invention of "IMPROVEMENTS IN STEAM ENGINES AND IN PROPELLING VESSELS;"
in which said Letters Patent is contained a proviso that I, the said Robert
Griffiths, should cause a particular description of the nature of my said
Invention, and in what manner the same is to be performed, by an instrument
in writing under my hand and seal, to be inrolled in Her said. Majesty's
High Court of Chancery, within six calendar months next and immediately
after the date of the said in part recited Letters Patent, as in and by the
same, reference being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, 1, the said
Robert Griffith, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, are fully described
and ascertained in and by the following statement thereof, reference being
had to the Drawings hereunto annexed, and to the figures and letters marked
thereon, that is to say:-
The nature of my Invention consists in the following improvements:―
First, in the application of toothed wheels, known by engineers as the
sun and planet motion, for increasing the speed of the propeller shaft
from the engine.
Second, in the application of one or more air pumps to boat engines, for
equalizing and regulating the motion and power of the machinery.
Third, in indicating the.. forces..of_the_various currents produced by a
vessel's passage through the water, at the position of the propeller for
governing the formation of the intended blades.
Fourth, in the construction of propellers for vessels as herein described,
reference being had to the Drawings hereto, annexed, and to the letters
marked thereon, similar letters of reference being used to denote similar
parts in all the Drawings.
Drawing A, Figure 1, represents a side elevation of a boat engine fitted
the sun and planet motion wheels a, a, of similar dimensions, by which
the propeller shaft is driven two revolutions by one double stroke of the
engine. The respective dimensions. of the sun and planet wheels may be
varied at pleasure according to the required speed of the propeller shaft.
I would here remark, that I am aware that the sun and planet motion has
long been applied to steam engines instead of the crank; I would have it
understood, therefore, that I do not claim the application to engines,
except only when applied to the propelling of vessels. B, an oscillating air
cylinder, placed at an angle,, worked by the crank pin c on the planet
wheel, in which air is compressed by the engine at the most effective
positions of the connecting rod d; during the stroke of the piston the elastic
force of the air so compressed is given out again to the crank pin on the
planet wheel, at the most ineffective position or dead point of the connecting
rod, by which the power exerted upon the propeller shaft is equalized
throughout the entire stroke of the engine, and regularity of motion preserved.
I am aware that air has been compressed in cylinders in a similar manner
as a substitute for fly-wheels in stationary engines; I do not therefore
claim this as my Invention, except the application.of to machinery when
employed in propelling vessels; nor do I confine myself to employing coni-

page_text: pressed air, as air pumps may be employed for the same purpose, working
a vacuum.
Drawing B shews the third part of my Invention. Figure 1 is an end
view; Figure 2, side view; Figure 3, plan of the after part of a vessel, shewing
the indicating apparatus for ascertaining the currents at the intended
position of the propeller when the ship is towed or sailed through the
water. For this purpose a, a, a, a,. a, are spheres attached to one end
of each of the transverse rods b, b, b, b, b, secured to upright spindles
c, c, c, c, c, leading on deck; to the top of the spindles c, c, c, c, c, are fastened
more transverse rods equal and similar to the lower ones b,. b, b, b, b;
attached to these top transverse rods are the spring balances d, d, d, d, d,
which correctly shew the pressure or resistance of the water against the
submerged spheres a, a, a, a, a, these being placed in the intended line
of the propeller indicate faithfully the force of the currents at their re-
spective positions, and by which I ascertain the correct form to twist
the blades of every propeller suitable to the lines of the vessel for which
it is intended.
Drawing C, Figure 1; shews a side elevation, and Figures 2 and 3
longitudinal and transverse sections, of my improved propeller, the centre
of which consists of a hollow metal sphere a; in which is placed the boss b
with sockets to receive the shanks of the blades c, c, secured therein by
the lever arms 'd, d, having lateral play in the socket of the boss b. The
outer ends of these arms act upon the sliding box e, which moves longitudinally
on the shaft against the collar g held by the lever h, which is connected
to the governor spring by the rod I, having an adjusting screw L. The
action of this arrangement is as follows: When the propeller is set to work,
the leading portion of the blades meet with greater resistance than the
after part according to the velocity it is driven, inducing the blades, by
the amount of this extra pressure upon their leading sides, to increase
the augle or pitch forward, causing the lever arms d to press forward the
sliding box e, which rotates against the collar g; this sliding motion is
controlled by the spring K, placed within the engine room or other suitable
position, which is regulated to the proper resistance by the adjusting screw
L on the rod I. Now, whenever the propeller meets with less resistance
5 from favorable winds or currents, the speed of the engine encreases, and
the increased speed of the propeller throws a proportional increasing pressure
on the leading side of the blades greater than the adjusted resistance of
the governor spring K, which is compressed by the rod I, forced forward

page_text: by the sliding box e against the collar g; the pitch increases until the
propeller throws a greater load on the engine and reduces it down again;
the number of revolutions instantaneously with which. the differential pressure
between the leading and after portions of the blade is diminished, and
the governor spring K,.forcing back. the sliding bar e, adjusts the true pitch
of the propeller to the power and proper speed of the engines, which by
this means have always their full effective power made available under
all circumstances of currents and winds. I am aware that it has been. before
proposed to alter the pitch of screw propellers when working; I do not
therefore claim this as my Invention, except when self-acting, as herein
described.
By the filling up of the centre portion of the propeller, the prejudicial
centrifugal action upon the water, and consequent waste of power, is avoided,
and the propeller strengthened; and although I prefer the form of a sphere,
as shown in Drawing C, the same may be accomplished in a conical egg or
other suitable form, or may be made cithér as shewn entirely on the propeller
shaft, or with a centre portion only attached to the propeller, the ends being
fixtures to the dead wood and stern post. I do not confine myself to the
precise method of filling up the centre of the propellor, so long as the peculiar
nature of this part of my Invention be retained.
Figure 4 represents the blades C, C, of a propeller inclined forward towards
the vessel; this form I have found most suitable for full sterned ships.
Figure 5 represents a propeller, the blades of which are made open in the centre.
Figures 6 and 7 represent an end and longitudinal elevation of a propellor
having four blades, two being inclined forwards, the other two backwards.
Figures 8 and 9 represent two views of the ordinary form of propeller, fitted
with my improved centre; and Figure 10, my improved tapered blades, with
the ordinary boss.
The blades c, c, of Figures 1, 2, 3, 4, 5, 6, and 7, are shewn as in Figure 10,
tapered towards their outward extremities, which I find in practice to be the
best form; the same, however, may be varied, as well as the position of the
shank C, which may be placed behind the centre of the blade when it is
desirable to increase the pressure of the leading side against the governor
spring K, as described with respect to Figures 1, 2, and 3, in Drawing C.
Having now described the nature of my Invention, and the manner in which
the same is to be performed, I would have it understood that I do not confine
myself to the precise details herein described, provided the. peculiar character
of either part of my Invention be retained; but what I claim is,-

page_text: First, the application of the sun and planet motion as a substitute for the
crank to engines when employed in propelling vessels.
Second, the application of air pumps for equalising and regulating the
motion of engines when employed in propelling vessels as herein described.
Third, I claim the principle of ascertaining, by indicating apparatus, the
most suitable form of propellers to the lines of the vessels for which they are
intended, and making the blades accordingly.
Fourth, I claim the self-regulating pitch of the propeller to the power of
the engine under all circumstances of wind or currents.
Fifth, I claim the filling up the centres of propellers as herein described in
contradistinction to and beyond what has been heretofore practised in forming
their centres or bosses.
Sixth, in forming propellers as described in respect of Drawing C,
Figures 4, 5, 6, and 7.
And, lastly, I claim the making of propellor blades narrower or tapered
towards their outside extremities in contradistinction to the form hitherto
adopted of increasing the width of that part of the blade.
In witness whereof, I, the said Robert Griffith, have hereunto set my
hand and seal, this Thirteenth day of March, in the year of our Lord
One thousand eight hundred and fifty.