IMPROVEMENTS IN THE GENERATION OF STEAM, AND ON THE APPLICATION OF STEAM OR OTHER POWER TO NAVIGATION
Year: 1838

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MELVILLE, of Upper Harley Street, in the County of Middlesex, Esquire, send
greeting.
WHEREAS Her present most Excellent Majesty, by Her Letters Patent
under the Great Seal of Great Britain, bearing date at Westminster, the Eighth
day of February, in the first year of Her reign, and rescaled on the twenty-sixth
day of the same month of February, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Melville, Her especial license, that I,
the said John Melville, ny exors, adiñors, and assigns, or such others as I, the
said John Melville, my exors, adiñors, and assigns, should at any time agree
with, and no others, from time to time and at all times during the tern of
years therein expressed, should and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick upon Tweed, my Inven-
tion of "IMPROVEMENTS IN THE GENERATION OF STEAM, AND ON THE APPLICATION OF
STEAM OR OTHER POWER TO NAVIGATION;" in which said Letters Patent there is
contained a proviso obliging me, the said John Melville, by an instrument under
iny hand and seal, particularly to describe and ascertain the nature of my said
Invention, and in what manner the saine is to be performed, and to cause the
same to be enrolled in Her Majesty's High Court of Chancery within six
months next and immediately after the date of the said Letters Patent, as in

page_text: and by the same, reference being thereunto had, will more fully and at large
appear; and whereas upon the application of me, the said John Melville,
Sir John Campbell, Knight, Her Majesty's Attorney General, by a certificate
under his hand, dated the First day of May now last, and addressed to the
Clerk of the Patents, did certify that he had granted leave to me, the said
John Melville, to file a memorandum of alteration of the title of my said Inven-
tion, pursuant to the Statute mentioned in such certificate, and by which
memorandum I, the said John Melville, altered the title of my said Invention
from "Improvements in the Generation of Steam, and on the Application of
Steam or other Power to Navigation," to "Improvements in the Generation of
Steam, and in Propelling Vessels by Steam or other Power."
NOW KNOW YE, that in compliance with the proviso in the said Letters
Patent, and herein-before mentioned, I, the said John Melville, do hereby declare
that the nature of my Invention consists in lessening the great expense attend-
ing the constant consumption of fuel in steam navigation by means of, first,
improvements in the apparatus for generating steam; secondly, in the adoption
of a chemical process (which improvements and process are applicable in the
generation of steam for other purposes as well as for navigation); and, thirdly,
by means of propellers. And first, as to my improvements in the apparatus
for generating steam, which will be best understood by the annexed Drawing
and the references thereto.
Figure 1 is a ground plan of the boiler, where A is the furnace. B, B,
the tubes, through which the fire or hot air passes and communicates with
the flues C, C, returning through No 1 and passing through No 2 to the
chimney. D, D, are water spaces. b, b, are bars of the usual construction.
c, c, are hollow bars, hollow through their whole length, and open to the ash pit
below, and they should rise above the level of the fuel about two inches at the
least. These bars are perforated with holes on both sides for the purpose of
admitting air over the surfaces of the fire. d, d, is a cross hollow bar, having
air holes on one side only.
Figure 2 is a transverse section of the boiler, where the same letters indicate
the same parts.
Figure 3 is a longitudinal section. E indicates the steam box, and F the
steam pipe; the other letters indicate as before.
It is evident that these hollow bars, being elevated amidst the burning fuel,
will become greatly heated, and that the air which passes from the atmosphere
into the hollows of the bars and through the small holes, will reach the interior
of the furnace and pass over the surface of the fire at a very high temperature,

page_text: pur-
inflaming and consuming the volatile and gaseous products of combustion.
By this means a portion of combustible matter, which would otherwise be lost,
will be saved, and much of what now issues from the chimney as smoke will
be consumed. When deemed advantageous, an additional quantity of air may
be forced through the hollow bars by any of the usual means for that purpose.
By arranging the furnace and flues in such a manner that no portion of the heat
generated acts on a horizontal surface, incrustations aro avoided and one great
cause of the loss of heat obviated. It is obvious that when the water in the boiler
is in a state of ebbullition, that the calcareous, earthy, or other matter separated
during the progress of evaporation will not rest on the circular surfaces, but fall
into the water spaces D, D, where it will admit of easy extraction by the mud
holes H. I have thus described the whole of the furnace and flues, but I only
claim as my Invention the introduction of the elevated hollow bars for the p
pose of economizing fuel and facilitating the generation of steam in the manner
herein-before described. And, secondly, as to my improvements by chemical
process. Having found by experiment that carbonic acid existing in water in
a free state is one cause of the earthy salts adhering to the interior surfaces of
boilers, to prevent this adhesion I saturate the free carbonic acid either with
lime water or with other substances capable of neutralizing carbonic acid, or
with lime put into the water before the water is introduced into the boiler or
generator. The saturation of carbonic acid with lime water and other similar
neutralizing substances is well known, but I only clain as my Invention the
application of this chemical process to boilers, for the purpose of preventing
incrustation. I prefer lime because it is the cheapest article. And, thirdly, as to
the propellers, which will also be best understood by the annexed Drawings, and
the references thereto. Figure 4 shews two propellers connected. The same
letters apply to each propeller. A, the propeller or paddle; B, the guide rods
or connecting bars, to which the propeller A is fixed; C, the radius rods or beams,
which vibrate on the centre; D, the crank; E, the driving shafts; F, the
angular standard supporting the radius rods C at the centre H; G, the train
of wheels to communicate the motion from one shaft to another. The com-
munication of motion, it is obvious, can be made in various ways, but I prefer
the wheels, which I have found to answer well, as the most convenient and easy
in their application, universally understood, and most readily supplied or replaced.
A bare inspection of the Figure shewing the propellers connected, will render
their action apparent to any one in the least degree conversant with mechanical
arrangements. The two cranks, it will be obvious, pass in opposite directions,
one propeller leaving the water after having given its stroke, whilst the other

page_text: enters the water, thus keeping up an alternate and nearly continuous action in
propelling the vessel. The nature of the arrangements for giving motion to the
propellers and their modes of action are, however, so obvious to any practical
man, that I deem it unnecessary to detail them further. These propellers may
be applied at comparatively small expence to ordinary sailing vessels, as they
require no outward bearings, so that every sailing vessel may also be made a
steam vessel at pleasure. The propellers are of such a construction that when
there is a sufficiency of wind and the expenditure of steam becomes unneces-
sary, the propellers are entirely out of the water, without removing, shifting, or
altering any part, and they are always ready to be instantly brought into use,
and are no incumbrance or impediment to the vessel when she is under sail.
It is also evident that these propellers, being by their construction extremely
light, are susceptible of being put in motion by manual power (as well as any
other moving power), and are well adapted for use in calms and light weather by
ships carrying numerous crews, troops, or emigrants. I have thus described the
construction of the propellers, but I only claim as my Invention that simple
and economical arrangement and combination of the parts described by means
of which any outward bearing is unnecessary, and by means of which the
propellers have an action nearly continuous, and yet, when not required to
be used, are kept entirely out of the water, so as to render it unnecessary to
alter, shift, or remove any part. I therefore claim as my Invention, first, the
aforesaid improvements in the apparatus for the generation of steam; second, the
aforesaid improvements in the generation of steam by chemical process; thirdly,
the aforesaid improvements in propelling vessels by steam or other power; and
such my
Invention being, to the best of my knowledge and belief, entirely new and
never before used within that part of Her Majesty's United Kingdom of Great
Britain and Ireland called England, Her said Dominion of Wales, and Town of
Berwick upon Tweed, I do hereby declare this to be my Specification of the
same, and that I do verily believe this my said Specification doth comply in all
respects fully and without reserve or disguise with the proviso in the said
herein-before in part recited Letters Patent contained. Wherefore I hereby
claim to maintain exclusive right and privilege to my said Invention.
In witness whereof, I, the said John Melville, have hereunto set my
hand and seal, this Eighth day of August, One thousand eight hundred
and thirts eight
J. (L.B.) MELVILLE.

page_text: AND BE IT REMEMBERED, that on the Eighth day of August, in the
year of our Lord 1888, the aforesaid John Melville came before our said Lady
the Queen in Her Chancery, and acknowledged the Specification aforesaid, and
all and everything therein contained and specified, in form above written.
And also the Specification aforesaid was stamped according to the tenor of
the Statute made for that purpose.
Inrolled the Eighth day of August, in the year of our Lord One thousand
eight hundred and thirty-eight.

page_text: In the Matter of the Patent granted to John Melville, of Upper
Harley Street, in the County of Middlesex, Esquire, for his Inven-
tion of "IMPROVEMENTS IN THE GENERATION OF STEAM, AND ON THE
APPLICATION OR OTHER POWER TO NAVIGATION," bearing date at
Westminster, the Eighth day of February, in the first year of the
reign of Her present Majesty.
MEMORANDUM OF ALTERATION of the title of the said Patent proposed
to be entered by John Melville with the Clerk of the Patents of
England, pursuant to an Act passed in the 5th & 6th year of His late
Majesty's reign, entituled "An Act to amend the Laws touching Letters
"Patent for Inventions."
I, the said JOHN MELVILLE, am advised and believe that I cannot specify my
Invention under the present title of my said Patent, because in the latter part
of the present title of my said Patent I stated that my improvements were in
the application of steam or other power to navigation, that is, in the moving
power, whereas, in fact, my improvements are not in the moving power, but
in the motion, that is, in propelling. I therefore alter the title from "Improve-
"ments in the Generation of Steam, and on the Application of Steam or

page_text: "other Power to Navigation," to "Improvements in the Generation of
"Steam, and in propelling Vessels by Steam or other Power."
In witness, I, the said John Melville, have hereunto set my hand, this
80th day of April. 1888.