CERTAIN IMPROVEMENTS IN ROTATORY STEAM ENGINES
Year: 1839

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
DICKSON, of Brook Street, Holborn, in the City of London, Engineer; send
greeting.
WHEREAS Her present most' Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Sixth day of March, in the second year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said John
Dickson, Her especial licence, full power, sole privilege and authority, that I,
the said John Dickson, my exors, admors, and assigns, or such others, as I, the
said John Dickson, my exors, admors, 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 "CERTAIN IMPROVEMENTS IN ROTATORY STEAM ENGINES;" in which
said Letters Patent is contained a proviso that I, the said John Dickson,
shall cause a particular description of the nature of my said 'Invention, and
in what manner the same is to be performed, 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.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Dickson, do hereby declare that my Improvements in Rotative Steam
Engines are described in the Drawings, Figures 1 and 2, as,attached to this
Specification.

page_text: A the induction pipe for conveying the steam from the boiler to the box
holding the slide valve B; C, C, C, the apertures for conveying the steam to
ana from the internal cylinder, as it may be required to work the engine;
D the internal cylinder for receiving and delivering the steam to and from the
apertures; E the eduction pipe for conveying the steam into the open air,
or a condenser; F, F, the abutments used for the steam to act on whilst it is
propelling the piston forward with the work in the steam cylinder or ring
U, one of which abutments is raised to allow the piston to pass it, whilst the
other is shut; the motion of the abutments as described are continued
alternately during each revolution the piston makes; G, eccentric for
working the said abutments by means of the two small levers H, H, with
their sundry apparatus attached thereto, the eccentric being fixed on the niäin
shaft I, it revolves with the internal cylinder and piston attached, thereto.
The piston K is metallic and has a spring acting on two wedges for the. purpose
of keeping the metals extended to their places in the cylinder, so as to. be
steam-tight; the covering plate is supposed to be taken from the piston for the
purpose of shewing the above arrangement; L, L, the plummer blocks for
carrying the centre shaft, to which is attached the work; M, M, M, M, are
soft packings placed in cavities which surround the internal cylinder. for the
purpose of keeping the same steam-tight, beyond the range of the piston;
N, N, N, N, are metal rings placed against the soft packings and acted on by
the pins 0, 0, 0, 0, for the purpose of tightening those packings when
required; P, P, are two boxes surrounding the said pins O, Q, and which can
be taken out of their places at all times when it is found necessary to repair
the soft packings without displacing any other part of the engine; Q. Q. are
two stuffing boxes surrounding the rods. R, R.. for the purpose of "Keeping
them steam-tight when opening and shutting the said abutments; S, S, are
two guides for the motions from the eccentric to the levers H, H; T, rack,
pinion, handle, and rod, for moving the slide B upon its face for the purpose
of stopping, starting, or reversing the motion of the engine, as no other
working valve is required. The same letters are referred to in both views
of this engine.
I hereby claim as my Invention that part of the arrangement called the
internal cylinder, as affixed to the main axis, and composed of two cavities
for conveying the steam from the boiler, for the purpose of acting on the
piston, and likewise for the purpose of making its escape into the open air or

page_text: to a condenser, as this engine may be worked either as a high or low pressure
engine.
I also claim that part called the nozel, on the end of which is placed a three-
holed slide, to be used for the purpose of starting, stopping, reversing, or
entirely shutting off the connection between the engine and boiler. This
nozel has three cavities therein, corresponding with the three-holed slide; one
for ingress, another egress, the third allowing the escape under the slide, either
into the open air or into a condenser; also a box which comes in two parts
in the end of the said nozel, for the purpose of getting at the packings which
fill the cavities for the purpose of keeping the internal cylinder steam-tight;
these packings may be made either of soft elastic materials or of metal.
the steam piston K, as shown in Figure 2, which is wholly composed of metal
with rounded corners, two wedges and one spring, for the purpose of keeping
the metals extended to their places in the cylinder, so as to be steam-tight.
See. the Drawings, Figures 1 and 2.
Also
In witness whereof. I the said John Dickson have hereunto set