IMPROVEMENTS IN DYNAMIC VALVE GEAR, APPLICABLE TO LOCOMOTIVE, MARINE, AND OTHER
Year: 1859

page_text: LETTERS PATENT to John Wesley Hackworth, of Priestgage Engine
Works, Darlington, Engineer, for the Invention of "IMPROVEMENTS IN
DYNAMIC VALVE GEAR, APPLICABLE TO LOCOMOTIVE, MARINE, AND OTHER
Scaled the 17th April 1860, and dated the 26th October 1859.
PROVISIONAL SPECIFICATION left by the said John Wesley Hackworth
at the Office of the Commissioners of Patents, with his Petition, on the
26th October 1859.
1, JOHN WESLEY HACKWORTH, of Priestgate Engine Works, Darlington,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN DYNAMIC VALVE GEAR APPLICABLE TO LOCOMOTIVE, MARINE, AND OTHER
ENGINES," to be as follows, viz. :-
This Invention relates to improvements in the arrangement of mechanism
for working the valves of locomotive, marine, stationary; and other engines,
requiring frequent reversal.
One arrangement of this gearing as applied to a direct acting horizontal
engine may be effecied as follows:-On the main shaft of the engine, side by
side with the driving crank, I place an eccentric pulley; the extreme throw of
which is directly opposite the extreme throw of the driving crank, so that the
circle described by each revolution of the driving crank shall always be
diametrically opposite to that described by each revolution of the extreme
throw of.the eccentric pulley, the throw of which must exceed the traverse of
the valve. I embrace the eccentric pulley with straps of the usual description,
attached to which is a rod of moderate length, having at its extreme end an

page_text: eye or joint connected to the pin of a sliding block, which moves in a groov
T-headed spanner or lever formed on or fastened on to the end of a shaft, th
said shaft being supported in bearings, the centres of which are equal to th
distance of the extreme centres of the eccentric rod, and directly above th
main shaft. Further, at about the distance of one-third of the length of th
eccentric rod from its extremity or any other proportion suitable for lap an
lend, attach laterally one end of a horizontal rod, the other end of which i
coupled to the valve strap or spindle. It follows then that when the slide
block to which the eccentric rod end is connected is guided vertically in the
grooved T-headed spanner or lever the oscillation at that point of the eccentric
rod to which the valve rod is attached horizontally will be equal to about one
third of the throw of the eccentric, in other words equal to lap and lead: this
then constitutes lead motion, and as the extremes of this movement take
place when the engine is on the centres, it is suitable for either back o
forward way round. Again, as the T-headed reversing spanner or lever may
be thrown into any angular position either to right or left by suitable levers
and rods attached thereto, the reverse motion is thus produced whereby a
variable and reverse lateral movement is imparted to the eccentric rod end, and
a proportionate movement to the valve, which I designate variable traverse
and reverse motion. When the valve is at the extreme point. of its throw with
the traverse motion it is not affected by the lead motion which is then
central, and vice versa, the extreme movements of the two being at right.
angles.
In locomotive engines, in order to preserve the centres of the grooved lever
or reversing shaft at all times equidistant from the centres of the driving shaft.
the bearings which carry the said grooved lever or reversing shaft are fixed to
the main bearings of the driving shaft.
The following is one arrangement for locomotive engines having outside
cylinders. The bearings which carry the reversing shaft are formed in the
ends of a parallel sliding frame extending across the boiler from side to side,
which frame is guided in two horns or guards at each side of the boiler having
two spring pins rising from the top of each bearing of the main or driving axle
to the under side of the said parallel frame, the bottom of which is formed to
receive the said spring pins. On the top of the frame at each end are mounted
the springs of the main or driving axle: the ends of these springs are secured
to wrought-iron columns fixed on the boiler, the top of which columns forms
the foundation of the horns or guards of the parallel frame. It is obvious
from this arrangement that the centres of the reversing shaft will be constantly
uniform with the centres of the main or driving axle.

page_text: Another part of my said Invention consists in having an eccentric rod to
work the lead notion, and another independant rod to work the variable
expansion and reverse motion, the latter rod being connected by a link or links
to the back strap of the eccentric, and having a corresponding link or links of
equal length with the former connecting it to the extreme end of the eccentric
rod, whereby the said rods are kept parallel with each other. I connect the
valve strap or spindle immediately to the link or links which connect the
extremity of the eccentric rod with the before named expansion or reversing
rod at any suitable distance for working the lap and lead. The back end of the
said expansion or reversing rod receives a sliding block, which works in a
parallel slot formed in the reversing shaft, or the rod end may slide on a pin
fixed in a loop formed in the reversing shaft, then, by throwing the slot of the
reversing shaft from the vertical to the angular position, either right or left,
the reverse motion will be effected, and the engine caused to move, either back
or forward way round as may be desired.
One distinctive feature in the principle of my Invention, is that of deducing
two motions from one eccentric crank or radius pin at right angles with each
other, whereby each. independently of the other. yields at the proper time its
full quota of movement to the valve.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Wesley Hackworth in the Great Seal Patent Office
on the 25th April 1860:
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
WESLEY HACKWORTH, of Priestgate Engine Works, Darlington, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of October, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, given and grant unto me,
the said John Wesley Hackworth, Her special licence that I. the said
John Wesley Hackworth, my executors, administrators, and assigns, or such
others as 1, the said John Wesley Hackworth, my executors, adminis-
trators, 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

page_text: Man, an Invention for "IMPROVEMENTS IN DYNAMIC VALVE GEAR, APPLICABLE TO
LOCOMOTIVE, MARINE, AND OTHER ENGINES,". upon the condition (amongst others)
that I, the said John-Wesley Hackworth, 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 John Wesley Hackworth, do hereby
declare the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings and
to the letters and figures marked thereon, that is to say:-
My Invention consists, firstly, in the construction and combination of
mechanism for working the valves of locomotives, marine, and other engines,
whereby any desirable amount of lead, or advance, variable expansion, or
cut-off and reverse action may be obtained from one eccentric, crank, or
radial pin, by two motions at right angles to each other. The rod or rods,
which are attached to the said eccentric crank or radial pin, maintaining for
both back & forward way round, one general and uniform centre line, only
deviating therefrom by an equal oscillatory movement on each side of the
centre line of action, from which oscillatory movement the motion of the valve
or valves is derived.
My Invention consists, secondly, in the construction and combination of
mechanism for admitting the steam or other fluid into the cylinder or cylinders
at the same elasticity or pressure as that which is contained in the boiler or
reservoir, the quantity or charge of the said steam or fluid being-regulated or
proportioned to the amount of work which the engine has to perform, by
increasing or reducing, or suspending completely one of the two right-angle
movements. The increase may be accomplished by moving the hand or
reversing lever to its greatest extreme on either side of its centre of move-
ment, whilst the reduction or suspension of the motion is performed by moving
the hand or reversing lever towards or into the centre -of-its-traverse.. TT
Thirdly, in the application of this valve gearing to engines requiring
uniformity of speed in one or both directions. The admission of steam or
other fluid may be controlled by a governor, leaving the reverse action only
to be effected by the hand or reversing lever.
One part of my said Invention, as herein set forth, may be described as
consisting of an eccentric rod of moderate length, one end of which is formed

page_text: into straps or clasps, which embrace an eccentric pulley secured to the main
or driving shaft of the engine, the other end of the said eccentric rod being
hinged, jointed, or attached by suitable arrangements to the pin of a sliding
block, fitted to move freely the full throw of the eccentric pulley in a plane,
the axis of which may, for the present, be said to fall through the centre of
the main or driving shaft. At about two-thirds of the length of the eccentric
rod from the centre of the straps, or one-third from the end of the eccentric
rod attached to the sliding block, or any other proportion suitable for lap &
lead, 1 attach laterally, and directly at right angles with the axis of the before-
described plane, one end of the valve rod, the other end of the said valve rod
being connected to the valve strap or spindle; hence it follows, that when 'a
rotary action is imparted to the eccentric pulley, the eccentric rod performs
the functions of a lever, the fulcrum of which is the sliding block moving in
the before-named plane, thereby communicating a certain proportion of the
oscillatory action of the eccentric rod, which is derived from the throw of the
eccentric pulley to the valve, being, in fact, equal to lap & lead. This con-
stitutes that which is termed the lead motion of the valve, and as the extremes
of this movement occur when the engine is on the centres, it determines the
relative position of eccentric & main crank, & is suitable for either back or
forward way round.
The plané has hitherto been treated as fixed in a position central to that it
will now be assigned to move in. This plane may take the form of a slot hole
ent through a shaft, or any other of the forms or modifications shewn in the
accompanying Drawings. The said shaft on which the before-named plane is
formed is supported in bearings, the centres of which are placed at a distance
from the main or driving shaft of the engine, equal to the extreme centres 'of
the eccentric rod. Further, this said shaft, with the before-named plane
formed on or attached thereto, may, with suitable rods & levers, be thrown to
an angle of about 40 degrees on each side of the previously assigned centre
line, or any other intermediate angular position, imparting through the mediuni
of such angular variation a variable & reverse lateral movement to that end
of the eccentric rod moving in the herein-before described plane, and thereby,
a proportionate movement to the valve.. This, then, is that part of my 'said
Invention which 1 designate variable traverse & reverse motion, the greatest
extremes of which are produced when the lead motion is in the centre of its
action, and vice versa, the two movements being at right angles each to each.
In circumstances in which the main or driving shaft constantly changes its
position, as in locomotive engines, the reverse movement shaft on which the
previously described plane is attached, will require to be fixed or attached tq

page_text: the bearings of the main or driving shaft, in order to preserve the centres of
the two shafts, namely, the reverse movement, shaft and the main driving shaft
of engine constantly equidistant from each other. The principles of action in
this modification are precisely similar to those already described. & previously
set forth in the foregoing description.
Another part of my said Invention consists in having an eccentric rod to
work the lead motion, & another independent rod to work the variable
expansion & reverse motion, the latter rod being connected by a link or
links to the back strap of the eccentric straps, which embrace the eccentri.
pulley, & having a corresponding link or links of equal, length with the fornier
connecting it to the extreme end of the eccentric rod. whereby the said rods
are kept parallel with each other. I connect the valve strap or, spindle
immediately to the link or links, which connect the extremity of the eccentric
rod with the before-named expansion or reversing rod at any suitable distance
for working the lap & lead. The back end of the said expansion or reversing
rod receives a sliding block, which works in a parallel slot formed in the plane
on the reversing shaft, or the rod end may slide on a pin fixed in a loop plane
formed in the reversing shaft; then by throwing the plane on the reversing
shaft to an angle of about 40 degrees on either side of the centre line, or any
other intermediate angular position, through the medium of such angular
variation, a variable & reverse lateral movement is produced, causing the
engine to move either back or forward way round.
Another part of my said Invention consists in its application to the governor
of any engine where uniformity of motion is required in one or both directions
whilst admitting the steam, fluid, or liquid into the cylinder, at the same
density or elasticity as that contained in the boiler or reservoir, that is, the
amount of the admission of steam, being proportioned to the duties the engine
is required to perform. The governor is an ordinary ball governor, the spindle
of which is mounted on a footstep in the base of a swan-neck standard which
has an eye at the top to hold the spindle erect. The swan-neck projects a
little past the eye to form a base for an inverted carriage, which supports one
end of a horizontal shaft, the other end of which may be carried to any con-
venient situation for the engine man, and has on its extreme end a circular
notch plate firmly fixed by a square and nut. The said shaft is encased in a
tube, on one end of which is formed a spiral working into the sector of a lever
keyed on the end of the reversing shaft. A hand spanner, or reversing lever,
is fixed on the end of the spiral tube with a spring latch or slot to fall into the
notch plate on the end of the horizontal shaft, whereby the spiral tube is made
to turn with the said shaft, both of which are supported by a standard within

page_text: the handle. It follows from this arrangement, that the spiral can be disengaged
from the horizontal shaft, and the engine reversed by the man at pleasure.
There are two loose bevil or mitre wheels on the governor spindle gearing with
one keyed on the end of the horizontal shaft, a fourth bevil wheel, for driving
the governor, is fixed on the spindle (immediately below the lowest loose one)
and gears with a corresponding bevil wheel carried by a stud shaft secured to
an arm cast on the swan-neck standard, the last named bevil wheel has a bolt
pulley attached to it which is driven by strap from a suitable pulley on the
engine shaft. There is a fricton clutch. coned at each end, whch is made to
turn with & slide on the governor spindle betwixt the two loose bevil wheels,
cach wheel having a counterpart to fit the coned clutch: the said coned, clutch
is coupled to the slide that is attached to the radius rods, and is made to move
up & down simultaneously by the action of the balls. The union may be
effected by an external tabe or governor spindle, or by making the governor
spindle hollow at that part. and introducing, a solid spindle with proper cross-
keys to unite the slide & clutch. When the engine is moving below its
proper speed, the balls of the governor press the friction clutch into the concave
horizontal shaft, which also moves the spiral thereon driving the sector round
& with it the reversing shaft to its furthest extreme where the stop arrests
its further movement, in which case the friction cone revolves in the convex
of the wheel without moving it. It is obvious, that in the circumstances [
have described, if the engine were reversed the action of the governor (which
would also be reversed) would drive the sector against the stop at the opposite
extreme, which. in both cases, would admit the greatest charge of steam.
When the engine exceeds the proper speed. the action of the governor balls
presses the coned clutch into the convex of the upper loose bevil wheel causing
it to turn & with it the spiral shaft in the contrary direction to that to which
it was driven by the lower bevil wheel, whereby the sector is turned, and with
it the reversing shaft, thus reducing the charge of steam, which can be carried
to such an extent as only to open the valve the lead." A similar effect is
performed when the engine is moving in the contrary direction.
In order that my said invention may be properly understood. I shall now
proceed to describe the several illustrative Figures upon the explanatory Sheets
of Drawings which have hereunto appended. for the purpose of shewing
certain modifications under which my improvements may be judiciously carried
out in practice. The Figures on Sheet 1 of the Drawings accompanying this
Specification illustrate certain modifications of my said Invention.
Figs. 1&2 on Sheet 1 shew a radius rod arrangement. Fig. 1 is an

page_text: elevation shewing the slide valve & cylinder face in section; Fig. 2 on
Sheet is a plan of the same. A is the main or driving shaft; B, the crank
attached thereto; C, the eccentric secured to the main or driving shaft, &
having its extreme throw directly opposite the extreme throw of the crank;
D, D, are straps embracing the said eccentric with projecting rod D', D¹, to
which one end of the valve rod is attached at H, whilst the other end of the
said valve rod is attached to the valve strap at I. thereby imparting the
oscillatory action of the said eccentric rod through the valve strap J to the
slide valve K; E is the weigh bar with projecting arms to which the radius
rods F, F, are attached; L is the reversing lever on the weigh bar E; M, one
end of the reversing rod:
Figs. 3&4 on Sheet shew an application of what is technically termed a
crouther" or "crowder" motion. Fig. 3 is a side clevation shewing the
valve & cylinder face in section; Fig. 4 is a plan of the same. A is the main
or driving shaft: B, the crank; C, the eccentric secured to the main or
driving shaft, and having its extreme throw directly opposite that of the crank;
D. D, straps embracing the eccentric with double rods D', D', to which one
end of the valve rod is attached with a single eye at H, whilst the other end
of said valve rod is attached to the valve strap J at I, thereby imparting the
notion of the eccentric rod to the valve K; E is the weigh bar; F, F, double
radius rods; N, N, motion links; L, reversing lever on the weigh bar E;
M. one end of the reversing rod.
Figs. 5&6 on Sheet 1 shew an application of parallel motion with double
radius rods, similar to a cranked axle, hinged or jointed on two bearings fixed
to reversing shaft which is also cranked, to clear the movement of the eccentric
rod. Out of the centre of the bow is projected a lateral standard, to which
two links forming a vibrating pillar for the main radius rod to swing upon,
whilst the opposite end is made to move lineally, guiding the extreme end of
eccentric rod by the contra-vibration of the double or cranked axle radius rod.
Fig. 5 is an elevation showing the valve and cylinder face in section; Fig. 6 is
a plan of the same. A is the main shaft; B, the crank; C, the eccentric
secured to main shaft, and having its extreme throw directly opposite that of
the crank; D. D, eccentric straps and rods, to which one end of the valve rod
is attached at H, whilst the other end of the said valve rod is attached to the
valve strap J at I, thereby imparting the action of the eccentric rod to the
valve K; E is the weigh bar; F, F, double radius rods; L, the reversing lever
attached to weigh bar E; M, one end of reversing rod; N, N, connecting
links; P, main radius rod.
of four hurrad avide for eccentric

page_text: rod end. Fig. 7 is an elevation shewing the valve and cylinder face in section;
Fig. 8 is a plan of same. A is the main shaft; B, the crank; C, the
eccentric attached thereto, having its greatest throw directly opposite that of
the crank; D, D, eccentric straps & rod, to which one end of the valve rod is
attached at H, whilst the other end of said valve rod is attached to the valve
strap J at I, thereby imparting the action of the eccentric rod to the valve K;
E is the weigh bar, which is cranked to clear the motion of the eccentric rod;
F, F, motion bars; L, reversing lever attached to weigh bar E; M, one end of
reversing rod.
Figs. 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 21, 22, 23, Sheet 2 of the
Drawings accompanying this Specification, shew certain constructive details
which may be employed in different arrangements. Fig. 9 is a front elevation;
Fig. 10, end elevation, & Fig. 11, plan of a cranked weigh bar E, having two
projecting arms F, F, for guiding eccentric rod end. A, crosshead with
square boxes H, H, connected by the pin 1, sliding upon the arms F. F.
Figs. 12 & 13 shew an elevation & plan of an eccentric & rod suitable for
the weigh bar & cross head arrangement described in Figs. 9, 10, & 11,
immediately preceding, the said eccentric rod being hinged to the pin 1;
Fig. 14, cross section; Fig. 15, longitudinal section; & Fig. 16, plan of
weigh bar E, with slot hole, guide plane for guiding eccentric rod end, and
sliding glut F, in two halves for introducing eccentric rod end I, these halves
being rivetted together.
Fig. 17. plan. & Fig. 18, elevation of a T-headed spanner or lever on
end of reversing shaft E, with dovetailed groove fitted with sliding glut F, and
pin I, for guiding eccentric rod end; Fig. 21, front elevation, Fig. 22, plan,
& Fig. 23, end elevation of slide guide, formed by a loop in reversing shaft.
through the centre of which the guide bar P is passed & secured by a nut,
washer, & pin at each end. The guide bar receives a square box H, having a
pin out at each side, running parallel with the reversing shaft E; the pins
1, 1, receive a double eye on the end of reversing rod, to which the guide
bar P& box impart variable expansion & reverse motion.
Figs. 19 & 20 on Sheet 2, shew another modification of my said Invention
with two rods. one for working the lead motion, & another for variable
expansion & reverse; Fig. 19 is a side elevation. Fig. 20 is a plan, shewing
the valve and cylinder face in section. A is the main shaft; B, the crank;
C, the eccentric, the extreme throw of which is directly opposite the extreme
throw of, the crank; D, D, eccentric straps; D. rod for working the lead
motion, attached to the links H, I, at one end, & to the eccentric straps at
the other; H, the rod for working variable & reverse motion, guided in the

page_text: slot P in the weigh bar E at one end. & attached to both links H, H, at
the other end; F, F. connecting links at the back of eccentric, answering to
H. H, at the opposite end, the said links F. F, & H, H, maintaining the
parallelism of the rods D & H; O, the valve rod, attached to the valve strap J.
thereby imparting the combined action of the two rods D & H to the valve K;
S. valve rod guide: L, reversing lever on the weigh shaft. E; M. reversing
rod end.
Figs. 24, 25, 26, & 27, Sheet 3, of the Drawings accompanying this
Specification, shew another modification of my said Invention as applied to
inside cylinder locomotive engines; Fig. 24 is a longitudinal section, Fig. 25.
plan of cylinder. valve gear, & crank shaft, partly in section; Fig. 26, front
elevation of valve gear, crank axle, reversing shaft. & driving wheels, partly in
section; Fig. 27, side elevation of axle guard with main bearing and reversing
shaft carriage attached. Figs. 24 & 25, A is the crank shaft; C, the eccentric ;
D, D, eccentric straps & rod; E, reversing shaft, with two slot holes for
guiding eccentric rod ends; 1 is the valve rod communicating with the
eccentric rod at one end, & the valve strap J at the other, thereby imparting
the action of the eccentric rod to the valve K; L is the reversing lever
attached to the reversing shaft; M, reversing rod; N, reversing lever.
Figs. 26 & 27. A is the crank shaft; D, D, eccentric rods; E, reversing
shaft: F. F. reversing shaft carriers attached to the main bearings R; L, the
reversing lever.
Figs. 28. 29, & 30, Sheet 3, shew another modification of my said Inven-
tion as applied to outside cylinder locomotive engines; Fig. 28 is a side
elevation, partly in section, Fig. 29. front elevation. Fig. 30, plan of one
end of reversing shaft frame. Fig. 28, A is the main shaft; B, the crank:
C, the radial pin; D, the eccentric rod, to which one end of the valve rod is
attached at H. & the other end I to the valve strap J, thereby imparting the
required motion to the valve K; E is the reversing shaft; F, the reversing
shaft frame extending across the boiler; L, reversing lover on the reversing
shaft M, reversing rod; N, reversing lever; P, sliding block, for guiding
eccentric rod end in slot hole through reversing shaft E.
main shaft; B is the crank; C, the radial pin; D. the eccentric rod; E, the
reversing shaft; F, the reversing shaft frame extending across the boiler:
I. reversing lever on the reversing shaft. Fig. 30, E is the reversing shaft;
F. the reversing shaft frame; P, sliding block for guiding eccentric rod end.
Figs. 31 & 32. Sheet 4, illustrate a modification of my Invention as applied
to engine governors. Fig. 31 is a side elevation, partly in section. & Fig. 32
is a plan of the same. A is the main or driving shaft of the engine: B, thy
Fig. 29, A is the

page_text: crank; C, the eccentric; D. eccentric straps & rod; H. 1. is the valve rod.
attached at one end to the eccentric rod. whilst the opposite end is coupled to
the valve strap J. & thus to the slide valve K; G, G. swan-necked standard
supporting the governor and bevil wheels: L. L. carriages for carrying
horizontal shafts M and O: R. projecting arm for stud pin shaft; S, governor
footstep: T, T. radius rods: V. coned clutch: W. upper, & X. lower loose
bevil wheels; Y. fixed bevil wheel on the horizontal shaft O; Z, fixed driving
bovil wheel on governor spindle: a. corresponding driving bevil wheel on
stud shaft: 6'. b'. driving pullies on stud & engine shafts: 0. horizontal shaft;
P, notch plate; d', spring latch: N, reversing lever: M. spiral tube: C. sector,
on the end of reversing shaft E; F, sliding block & pin for guiding eccentric
rod end.
Having now described and particularly ascertained the nature of my said
Invention. & the manner in which the same may be used or carried into
effect, either in engines worked by steam. air, or other elastic fluid, may
observe in conclusion that I do not confine or restrict myself to the precise
details or arrangements which I have had occasion to describe or refer to,
as many variations may be made therefrom without deviating from the
principles or main features of my said Invention; but what. I consider to be
novel & original, & therefore claim as the Invention secured to me by the
herein-before in part recited Letters Patent, is,-
Firstly, the arrangement & combination of machinery for deducing two
motion's from, one eccentric. crank, or radial pin; one motion for working that
which is termed the "lead" of the slide valve, and the other motion at right
angles with the former. whereby I obtain a variable expansion & reverse motion.
The full quota of motion from each being obtained independently the one from
the other, whilst the eccentric rod or rods maintain one general centre line, only
deviating therefrom by an equal oscillatory action on each side of the centre
line, from which oscillatory action the motion of the valve or valves is derived.
substantially as herein described and set forth.
Secondly, the arrangement & combination of mechanism, which term
the governor arrangement, applied to engines requiring uniform motion in one
or both directions. whereby the admission of steam. air, or other elastic fluid to
the cylinder or cylinders may be entirely controlled, regulated, & determined
in proportion to the amount of work the engine has to perform, substantially
as herein described & set forth.
Thirdly, the modification & arrangement as herein specified & illustrated
by Figs. 1 & 2, Sheet 1, of the Drawings hereunto attached.
Fourthly, the arrangement & combination as herein described, operating

page_text: in conjunction with a crowder motion (as it is technically termed), with double
radius rods, as delineated in Figs. 3 & 4, Sheet 1. of the Drawings accom-
panying this Specification.
Fifthly. the arrangement & combination of mechanism as arranged & opera-
ting together. with parallel motion & double radius rods, as herein described
& shewn in Figs. 5 & 6, Sheet 1, of the accompanying Drawings.
Sixthly, the modification & combination of mechanism as arranged & ope-
rating, with four-barred guide for eccentric rod end, herein described & shown
in Figs. 7 & 8, Sheet. 1, of the Drawings hereunto attached.
Seventhly, the modifications of constructive details, as illustrated & set forth
in Figs. 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 21, 22, & 23, of Sheet 2, of the
accompanying Drawings, and also the construction & combination of the several
parts, as herein specified.
Eighthly, the arrangement & combination of my Invention, operating &
applied as illustrated in Figs. 19 & 20, Sheet 2, of the Drawings hereunto
attached, wherein two rods are applied. one, D, for working lead motion, & the
other, H. for working variable expansion & reverse motion.
Ninthly, the modification & arrangement as applied to inside cylinders loco-
motives, substantially as herein described & shewn in Figs. 24, 25, 26, & 27,
Sheet 3, of the accompanying Drawings.
Tenthly. the modification, arrangement, & application of my Invention to
outside cylinder locomotives, operating as herein described & illustrated in
Figs. 28, 29, & 30, Sheet 3, of the Drawings accompanying this Specification.
Eleventhly. the modification, arrangement, & application of my Invention
to engine governors, operating substantially as herein described, & for the
purposes set forth & illustrated in Figs. 31 & 32, Sheet 4, of the accom-
panying Drawings.
In witness whereof. I, the said John Wesley Hackworth, have hereunio
set my hand and seal, this Twentieth day of April, in the year of our
Lord One thousand eight hundred and sixty.
Witness.
M. HUNTER.
JOHN WESLEY HACKWORTH. (L.S.)