IMPROVEMENTS IN APPARATUS FOR PRO- DUCING THE MORE COMPLETE COMBUSTION OF Gas, PARAFFIN, AND OTHER OILS IN LAMPS
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by Frederick Wilfred Scott Stokes at
the Office of the Commissioners of Patents on the 27th September 1881.
FREDERICK WILFRED SCOTT STOKES, of 40, Southampton Buildings, Chancery
Lane, in the County of Middlesex. "IMPROVEMENTS IN APPARATUS FOR PRO-
DUCING THE MORE COMPLETE COMBUSTION OF Gas, PARAFFIN, AND OTHER OILS
IN LAMPS."
My Invention relates to lamps or apparatus in which gas or inflammable oil is
burned for the purpose of obtaining light, and it has for its objects improved
methods of constructing parts of such apparatus so that more perfect combustion is
obtained, and thus great economy of the gas or inflammable oil is obtained, an
equal amount of light being produced with a less consumption of gas or oil.
My Invention is applicablo more especially to apparatus such as that known as
the Argand burner, in which a cylindrical flame is used, round and above which a
glass chimney is fixed.
At the upper end of such glass chimney so arranged I fit a transverse disc or
cover having an opening through its centre, preferably circular in shape, and of
less diameter than the top of the chimney, the size of the opening being pro-
portioned to the amount of light to be produced. By this arrangement the rapid
passage of air through the chimney is checked, and the combustion in the gas or
other flame is made more perfect, greater light being given, and economy being
attained. The disc may be made without an opening through it, but raised slightly
above the top of the chimney.
The disc or cover may be made of metal, talc, or other suitable material capable
of resisting the heat to which it is exposed, and it may be made with corrugations
which allow a small quantity of air to pass along them. I fit it to the top of the
chimney in any convenient way, as, for instance, by means of a flange fitting over
or upon the upper edge of the chimney, the disc or cover being itself either flat or
coned upward or downward more or less at its centre. Or sometimes I make the
cover form a part of the glass chimney itself, which may be made of less height
than is usually the case.

page_text: In some cases I make the opening through the disc variable in size, so that it
may be proportioned to the varying quantity of gas which is being burned, or to
other varying circumstances.
I prefer to do this by arranging two discs concentrically one upon the other, the
openings through them being made more or less elliptical, so that when the upper
disc is turned until the elliptical opening is at right angles to that in the disc
below, the central opening through them is considerably less in area than when
the upper disc is turned until the two elliptical openings coincide.
Instead of a central opening through the disc or cover two or more openings
may be used.
In addition to the method of arrangement as above described, by which the area
of the upper part of the chimney is contracted, I sometimes also contract the area
of the chimney below the gas or other flame, and a valve or valves may be used to
regulate the admission of air to the lower end of the chimney.
The openings in the different arrangements described may be varied in number
and shape to suit different circumstances.
In order to lessen the liability to fracture by heat of the glass chimneys arranged
as above described, or in the ordinary way, I sometimes make such glass chimneys
with helical grooves or marks made partly through their substance in such manner
that if the chimney cracks the crack will be induced to follow the grooves or
marks so made without the chimney necessarily falling to pieces or being rendered
useless.
For this purpose a groove or crack is made helically round the chimney.
Such groove or crack may be made whilst the glass is soft in the process of
manufacture, or_by_incans_of_a_diamond_when_the glass is cold, or in other con-
venient way.
Apparatus constructed according to my Invention-is-very-simply-and-cheaply
made, and durable, and by its use and the more perfect combustion obtained, great
economy is effected in the consumption and cost of the gas or inflammable oil used.