AN IMPROVED METHOD OF LIGHTING PLACES WITH GAS
Year: 1830

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MICHAEL
DONOVAN, of the City of Dublin, send greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Sixth day of October, in the first year of His reign, did,
for Himself, His heirs and successors, give and grant unto me, the said
Michael Donovan, His especial licence, sole privilege and authority, that
I, the said Michael Donovan, my exors, admors, and assigns, or such others.
as I, the said Michael Donovan, 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 mentioned, should and lawfully might make,
use, exercise, and vend, within England, Wales, and the Town of Berwick-.
upon-Tweed, my Invention of "AN IMPROVED METHOD OF LIGHTING PLACES
WITH GAS;" in which said Letters Patent is contained a proviso, that I, the
said Michael Donovan, 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 His 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, I, the said
Michael Donovan, do hereby declare that the nature of my said Invention,
and the manner in which the same is perforined, is described and ascertained
as follows:-
"
"
There are certain gases, which, although they burn, do so with the emission
of very little light, such are hydrogen gas, carbonic oxide gas, and that gas
which is produced by the chemical action of water or steam on red-hot coke or
charcoal. But these gases may each bo rendered highly luminous in burning
by mixing with them the vapour of certain volatile combustibles, such as spirit
of turpentine, or the oil or spirit which is obtained by continuing the distillation
of the resin remaining after spirit of turpentine has been distilled off in the
usual manner, or oil or spirit of vegetable tar, or coal naphtha or naphthaline;
I therefore use for that purpose any of the above-mentioned substances or
mixtures of them. When naphthalino is to be employed it is convenient that
it shall be dissolved in any of the above-mentioned liquids, and when oil or
spirit of vegetable tar or oil or spirit of resin is to be used for the solution of
the naphthaline the specific gravities that are herein-after indicated must be
employed. The oil or spirit of tar or of resin must always be well freed from
acidity by agitation with powder of chalk and water, and the coal naphtha
must be freed from ammonia by washing with water acidulated with sulphuric
acid, processes which are sufficiently well known. The manner of using these
volatile combustibles is to convert any one of them or mixtures of them into
vapour, to mix the vapour along with any of the gases already mentioned, and to
burn that mixture while it is issuing out of a proper burner. The method of
converting these volatilo combustibles into vapour is to expose large surfaces of
them to the action of the gas, at temperatures varying according to the nature
of tho volatilo combustible; coal, naphtha rendered in a high degree specifically
light by repeated distillations, will spontaneously be converted into vapour at
ordinary temperatures of the atmosphere and will mix with the gas, while coal
naphtha of greater specific gravity, and the other volatile combustibles above
mentioned, will require the aid of artificial heat applied to them in a proper
vessel, which I call a recipient, in order to convert them in sufficient quantity
into vapour. Tho heat which I prefer applying for converting the volatile
combustible into vapour is that arising from the burning of the gas when
issuing out of the holes in the burner; for if the burner be constructed as herein-
after described it will not only become very hot itself, but will communicate so
much of its hent throughout the whole recipient and its contents as will be fully
adequate to the gradual conversion of the volatile combustible into the state

page_text: of vapour, provided that extensive surfaces of the volatile combustible aro
exposed to the action of the heat at the same time that the gas is allowed to
pass through the recipient in contact with these surfaces.. New supplies of
gas, are to be made to enter the recipient as fast as the former ones have
passed out, and these new supplies of gas are to be allowed to mix with fresh
portions of the vapour
of the volatile combustible which are successively pro-
duced. The method which I prefer, of exposing extensive surfaces of the
volatile combustible to the conjoint action of the heat and of the gas, is to
cause a cylindrical roll, consisting of several convolutions of fine iron wire
gauze contained in the recipient, to be continually impregnated or moistened
with the volatile combustible by capillary attraction, and to pass the gas in
numerous streams through or over the wire gauze while the recipient and. its
contents are at the proper degree of heat. The degree of heat that will be.
communicated by the burner to the recipient. and it contents will depend upon
several circumstances; it will depend in a great degree on the nature of the gas.
Carbonic oxide will produce very little heat in burning compared with that.
produced by hydrogen, or the gas which arises from the chemical action of
water or steam on red-hot coke or charcoal; I. therefore prefer bydrogen, and
the gas arising from the chemical action of water or steam on red-hot coke or..
charcoal, as being capable of affording an adequate degree of heat. The
degree of heat that will be communicated by the burner to the recipient and
its contents will also depend on the size of the recipient as compared with the
number, width, and distance. from each other of the holes in the burner
through which the mixture of gas and vapour issues in order to supply the
flame. If the recipient be too small for the number, width, and distance from
each other of the holes in the burner, the recipient and its contents will become
so hot that too much of the volatile combustible will be converted into vapour
for the volume or bulk of gas which passes through, and then the mixture of
the
gas and vapour will give off much smoke in burning; on the other hand,
if the recipient bo too large compared with the number, width, and distanco
from each other of the holes in the burner,. the recipient will be heated too
feebly to convert a sufficiency of the volatile combustible into vapour, and then
there will be little light emitted during the combustion of the mixture of gas
and vapour. The heat of the recipient and it's contents will also depend on
the shortness of the neck or shank of the burner, for if there be a long neck
or shank, it will remove the recipient too far from the source of heat to receive
a sufficient supply. The effects of the heat communicated, by, the burner to
the recipient and its contents may be modified by the relative dimensions of the

page_text: cylindrical roll of wire gauze. The heat may be rendered less efficacious in
converting the volatile combustible into vapour by making use of a smaller
cylindrical roll, or the heat may be rendered more efficacious in that respect
by employing a larger cylindrical roll; and fine wire gauze promotes the con-
version of the volatile combustible into vapour more than a coarse one, the
circumstances of the wire gauze being every other way the same. The effects
of the heat communicated by the burner to the recipient may be further
modified by using a volatile combustible of less or greater volatility, or all
these methods of modification may be employed for the purpose together.
The foregoing are the general principles which are to regulate this improved
method of lighting places with gas.
I now procced to a particular description of the instruments by which these
principles are to be carried into effect. The circumstances are so various
under which this new method of lighting places with gas may be applied
that it is not possible to describe an instrument that without alteration will
answer every case. Suppose that the gas to be burned is derived from water
ncted upon by red-hot coke or charcoal; the nature of this gas will vary
according to the extent of red-hot coke or charcoal over which the stream of
water has been passed. The description of the following instrument is founded
on the supposition that the gas to be burned at the burner is generated by
passing steam through a cast-inctal tube or retort, the diameter of which taken
on the inside is eight inches, and the length of which that is to be heated red
hot in the furnace is three feet and a half. The portion of the retort that is
kept red-hot is to be filled with coke, and the coke is to be leated so as to
appear bright red in daylight; gas will be thus produced which will be capable
of burning with a brilliant white light when exposed to the action of the volatile
combustible in an instrument of the following dimensions and construction:-
Figure 1 is a section of the recipient and gas supply tube. The recipient
a, A, a, is a hollow brass cylinder, which when in use stands vertically.
The outside diameter of this cylinder is thirteen-fifteenths of an inch, the
inside diameter four-fiifths of an inch, the thickness of the brass which
composes the cylinder is one-thirtieth of an inch; the outside length or
height of the cylinder is two inches and five-sixths, of which the screw at
top occupies one-fifth of an inch. This cylinder is closed at its lower end
by a brass bottom soldered into it one-sixth of an inch thick, and in the
centre of the bottom is a female screw B, intended to receive any con-
nexion, such as a stop-cock or tube, that may be deemed convenient for
supplying the recipient with the gas intended to be burned. From the femalo

page_text: screw B ascends a small brass pipe C, which I call the " 'gas supply tube of
the recipient;" its use is to convey the gas into the recipient, its inside diameter
is three-sixteenths of an inch, and the thickness of the brass which composes
the tube is one thirty-second of an inch; its height from the inner surface of
the bottom of the recipient to which it is soldered is two inches and one-eighth.
There is another brass pipe entering laterally into the recipient near its bottom;
its use is to convey the volatile combustible into the recipient; a part only of
this tube is shewn in the Drawing; at its other end it communicates with any
general reservoir destined to contain the volatile combustible.
Figure 2 is a section of the brass cover of the recipient, the disperser, and
the burner. The cover A when in its place is screwed on the top A of the
recipient, Figure 1; it screws on so tight as to prevent the escape of gas; it
is one-third of an inch in height; from the centre of this cover rises the
burner B, the total height of which above the cover is five-sixths of an inch.
The diameter of the circle of holes in the rim B of the burner for the issue of
gas is to be eleven-twelfths of an inch; the number of these holes is to be
forty, of which twenty only are shewn in the Drawing; the diameter of cach
hole is to be one-fiftieth of an inch, the depth of the rim is to be three-six-
teenths of an inch, and its thickness is to be one-sixth of an inch. The air
passages of the burner are b, B. From the centre of this cover a tube C
proceeds downwards, which I call "the disperser;" it is a brass tube of
one-third of an inch inside diameter; the substance of the brass of which
the tube is made is one-thirtieth of an inch thick, it is soldered to the cover;
its bottom C is open, but it has an air-tight division of brass soldered in
at D, which prevents any gas that enters it from passing directly into the
burner. The disperser is perforated with numerous holes; thirty will suffico;
that is, three rows consisting of ten each; twenty only are shewn in the
Drawing; the diameter of each hole is to be about one twenty-fourth of an
inch; the length of the disperser is to be two inches and a half. From this
construction it is plain that when the cover A is to be screwed on A, Figure 1,
the dispenser slips over the gas supply tube and remains concentric with it
when both are in their place. In this position of the parts, if gas be passed up
through the gas supply tube it will issue through the open mouth C, Figure 1,
will enter the disperser placed over it, will pass out in all directions through
the thirty holes, being prevented from passing directly upwards by the division
at D, and it will pass out through five larger holes made in the disperser above
the division (two of which only are scen in the Drawing), and so escape
through the air passages of the burner; the five larger holes placed above the
division are each one-sixteenth of an inch in diameter. The disperser is to

page_text: have a piece of iron wire gauze rolled moderately tight round it, so as to form
a compact cylinder of wire gauze composed of several couvolutions; the wire
gauzo cylinder is then to be bound round with very thin wire at each end so
as to prevent its opening. When the disperser is in its
proper place in
the recipient the wire gauzo cylinder round it should be touching the bottom
of the recipient. The piece of wire gauze which composes the cylinder must
vary in its dimensions, according to the naturo of the volatile combustible to
be used. I here give the size of wire gauze that will be proper for four
different kinds of volatile combustible. The wire gauze must be made so that
thero will be sixty-one wires in the warp and the same number in the woof in
each square inch, and each square inch of the gauze is to weigh twelve grains
and five hundred and eighty-three thousandths of a grain. For oil or spirit of
turpentine the piece, of gauze that is to be rolled round the disperser is to be
four inches and five-twelfths long, and is to be one inch and thirteen twenty-
fourths broad; when rolled up the cylinder is to be in height equal to the
breadth of the gauze. For oil or spirit of tar of specific gravity 0-876, or
for oil or spirit of resin of specific gravity 0-870, the piece of wire gauze should
be four inches and five-twelfths long and one inch and fifteen-sixteenths broad;
and for coal naptha holding so much naphthaline in solution as brings its
specific gravity to 0.970 the piece of wire gauze should be six inches and one
twenty-fourth long and 'one inch and ten-twelfths broad; as to the mode of
supplying the volatile combustible to the recipient there may be various
constructions; I give a section of one in Figure 3, where A is the recipient;
B, the disperser; C, the gas supply tube; D, the brass reservoir for the volatile
combustible; E, the tube through which the volatile combustible flows into
the recipient; F, the tube that establishes the same pressure of gas on the
surface of the volatile combustible as exists in the recipient; G, the aperture
and screw plug through which the volatile combustible is poured in; II is the
burner; I is the aperture to adunit gas from the main supply. In this Figure.
to avoid confusion, the wire gaúzo cylinder has been omitted. The volatile
conibustible should never be allowed to flood higher than it would do in an
instrument of the dimensions represented in this Figure. It is obvious, from
what has been already described, that when the naphtha is so volatilo as to mix
with tho gas at the ordinary temperature of the air the burner need not
bo immediately connected with the recipient, and that, a tube of several feet
long may be interposed between the recipient and the burner. I have used
a tube of six feet long for that purpose, but it may be longer. And there-
fore I claim as my Invention the method of lighting places with gas by
mixing the vapour of any of the volatile combustibles above mentioned

page_text: with any
of the gases above mentioned, which mixture affords a good light
when applied to practice in the manner above mentioned.
In witness whereof, I, the said Michael Donovan, have hereunto set my
hand and seal, this Second day of April, in the year of our Lord One
thousand eight hundred and thirty-one.