IMPROVEMENTS IN STEAM ENGINES AND OTHER MECHA- NISM OF STEAM BOATS
Year: 1837

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, NEIL SNOD-
GRASS, of the City of Glasgow, in the County of Lanark, Engineer, send
greeting.
WHEREAS His late most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Fifteenth day of March, in the seventh year of Her reign,
did, for Himself, His heirs and successors, give and grant unto me, the said
Neil Snodgrass, His especial licence, full power, sole privilege and authority,
that I, the said Neil Snodgrass, my exors, adñors, and assigns, or such others
as I, the said Neil Snodgrass, 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, the Invention of "IMPROVEMENTS IN STEAM ENGINES AND OTHER MECHA-
NISM OF STEAM BOATS," being partly of my own Invention, and partly communi-
cated, to me by a certain foreigner residing abroad; in which said Letters Patent
is contained a proviso that I, the said Neil Snodgrass, shall cause a particular
description of the nature of the said Invention, and in what manner the same
is to be performed, to be inrolled in His said Majesty's High Court of Chan-
cery 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
Neil Snodgrass, do hereby declare the nature of the Invention, and the

page_text: 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 Drawing hereunto annexed, and to the figures and letters marked
thereon, that is to say:-
In the annexed Drawings Figure 1 exhibits a plan of two hollow conical
vessels a, a, a, about one hundred and ten feet long, and seven feet diameter
in the middle; they are made of malleable sheet iron; the tapered ends are
about an eighth of an inch thick, and the middle (which is cylindrical to the
extent of about forty feet) is formed of three sixteenths iron. To prevent
the loss of buoyancy, which might arise from leakage, cach of the hollow
conical vessels is divided transversely into compartments of about four feet
each (made air and water tight), by forming them at first in separate lengths,
and rivetting them together on hoops of angle iron. To stiffen the entire
vessels four malleable iron bars c, c, c, c, are rivetted thereto equi distantly and
longitudinally their whole length, and along the upper side of each of these
vessels is a beam of wood b, b, eleven inches by eight, which extends the
whole length of the lower deck, upon which the whole of the joisting and
beams for supporting the machinery and deck are bolted. d, d, the paddle
wheel, placed about five feet forward of the centre of the boat for the purpose
of keeping it on an even keel. e, e, are two helms steered by iron rods
(or chains) running on friction pulleys beneath the lower deck, and connected
by an upright shaft and bevil wheels to the pilot's steering wheel in front
of the boat on the upper deck (see Figure 3). f, f, f, f, are four diagonal
stays fixed to the beams or sides of the conical vessels below the joisting for
connecting these parts firmly together. Figure 2 is chiefly designed to
exhibit a plan of the lower deck, which is laid upon the joisting shewn in
Figure 1, and is caulked and tarred in the usual manner; this deck is sup-
ported by standards, pillars, and partitions. At h, h, h, is a promenade surround-
ing the deck; at m is the steerage or inferior cabin, and at the superior
cabin; k, k, l, k, represent four cylindrical boilers connected by a steam
pipe above, which is common to all of them, and provided at n with a large
safety valve, from whence there is a large tube to convey the waste steam
into the water reservoir below; at the lower part of each boiler is a pipe
provided with a two-way cock to feed or blow off each boiler, and in the
general steam pipe above are four valves through which the steam passes
from short vertical pipes leading from each boiler; by shutting any one of
these valves and the feed cock beneath appertaining thereto such boiler may
be detached, if required. 0, 0, represent a horizontal engine, which receives
the steam from the boilers and communicates motion to the paddle wheel

page_text: d, d. Figure 3 exhibits an elevation of the boat; p, p, p, the upper deck with
railing and seats; i, i, are stairs leading from the lower to the upper deck
on each side of the vessel; the pilot and steering wheel at the bow alluded
to under Figure 1. The connecting rod from the throttle or governor valve
in the steam pipe (see Figure 7) is conveyed by a lever to the pilot's hand, by
which he can at pleasure stop, lessen, or increase the speed of the boat.
r, r, the funnel placed astern to project the smoke clear above the vessel;
8, s, keels fixed under each of the conical vessels to strengthen and protect
them. Figure 4 presents an end view of the steam boat, shewing the iron
stays t, t, their connection with the conical vessels a, a, and the framework
above. Figure 5 exhibits a section of an engine cylinder in connection with
the improvements. u is the cylinder, and the piston; w, w, shew my
improved piston valves, and x, x, the improved nozzles. The valve pistons
are provided with metallic packing and springs. The seats for the pistons in
the nozzles are bored to rather more extent than twice the depth of the
pistons which work in them; and to cause the metallic segments to slide over
the edges of the passages without obstruction I form suitable bridges at y, Y,
against which the segments bear in their movements, and pass over quite
easily, and without that injurious wear to which other mechanism for the
purpose is subjected. In Figure 6 is shewn an external view of the cylinder
and nozzles as adapted to high-pressure engines. Figure 7 is designed to
exhibit an outline of the paddle wheel A, A, with an end view of the axle
and crank; fixed upon the axle behind the crank is a spur wheel (1) about two
feet and a half in diameter, which drives another similar spur wheel (2) turning
on a strong stud. The motion of this wheel (2) works the valves by means of
a connecting rod (3, 3,) in the usual manner, only having a stud pin screwed
to the side instead of the excentric usually fixed on the crank shaft of the
engine. The wheel (1) has two friction rollers (4, 4,) fixed by studs on the
pivots of which they move. These rollers alternately act against the perpen-
dicular lever (5, 5,) at the top of which is jointed a rod (6, 6,) which is
connected to the governor valve (7) placed in the common steam pipe that`
communicates with the valves of the engine cylinder. The rod (6) being
constructed in the manner shewn in the Drawing may be elongated or
contracted at pleasure, so as to adjust or cut off the steam at any part of the
stroke, and allow the steam to work expansively during the remainder of
the stroke, and thereby effect a saving in fuel. At (9, 9,) is another
governor valve and rod that is connected to the pilot's lever before referred to.
Having now explained in detail the several improvements in connection
with other mechanism that was previously in public use, I desire it to be

page_text: understood that I limit my claims of Patent right to the construction and em-
ployment of the air-tight conical vessels described at a, a, in Figures 1, 2, 3, 4,
or to other tubular or similar apparatus applied to a-like purpose..
I likewise claim the general arrangement of a steam boat described under
the same Figures.
I likewise especially claim the improved nozzles and piston slide valves
described in Figures 5 and 6, and the strike-off apparatus delineated in
Figure 7.
In witness whereof, I, the said Neil Snodgrass, have hereunto set my
hand and seal, this twelfth day of September, in the year of our Lord
One thousand eight hundred and thirty-seven.
This is the Specification referred to in the affidavit of Luke Hebert, sworn
this 15th day of September, 1837, before me,
W. WINGFIELD.
Luke Hebert, of Camden Town, in the county of Middlesex, Gentleman,
maketh oath and saith, that he is acquainted with the manner and character
of the handwriting of Thomas Baird, Esquire, a Justice of the Peace, residing
at Glasgow, in the county of Renfrew, within that part of the United Kingdom.
of Great Britain and Ireland called Scotland. And this deponent further saith,
that the name or signature "Thomas Baird," with the addition of "J. P.,"
set, subscribed, and written in the Specification marked A, hereunto annexed,
and dated the Twelfth day of September instant, and executed by Neil
Snodgrass, of Glasgow, in the county of Lanark, Engineer, whereby it is
stated that the said Specification was acknowledged by the said Neil Snodgrass
before the said Thomas Baird, on the said Twelfth day of September, at
Glasgow, in the county of Renfrew aforesaid, are of the proper respective
handswriting of the said Thomas Baird and Neil Snodgrass. And this deponent
further saith, that the said Thomas Baird, at the time of setting and subscribing

page_text: his name on the said Specification, in manner above stated, was and now is
one of the Justices of the Peace acting in and for that part of the United
Kingdom of Great Britain and Ireland called Scotland.