Improvements in Oil Lamps.
Year: 1898

page_text: Date of Application, 5th Mar., 1898
Complete Specification Left, 5th Dec., 1898—Accepted, 4th Mar., 1899
Improvements in Oil Lamps.
FRANK WILLIAM HARBORD, Surbiton House, Englefield Green, Surrey, Metal-
lurgical Chemist, GEORGE MINCHIN MINCHIN, Coopers Hill College, Englefield
Green, Surrey, Professor of Applied Mathematics, do hereby declare the nature
of this invention to be as follows:-
The object which we have in view is to provide a substitute for the ordinary
combustible wick of lamps; and for this purpose we fix above, and in intimate
contact with, an ordinary cotton or other wick, a plug of a suitable shape, according
to the form of the form of the burner, made of porous earth, preferably kieselguhr;
the whole to be fixed in a suitable carrier to allow of the adjustment of the
height of the flame. The cotton wick may be fixed permanently to the lower end
of the plug, or may be kept in contact by means of a pressure screw or other
suitable device.
The said porous plug may be baked at such a temperature as to insure cohesion,
or a little more fusible clay may be mixed therewith before burning to ensure
this object. The necessary adhesion may also be obtained by mixture with any
suitable agglutinising material, and the plug may then be burned or used in a
raw state, as found desirable.
Dated this 4th day of March 1898
FRANK WILLIAM HARBORD.
GEORGE MINCHIN MINCHIN.
Improvements in Oil Lamps.
FRANK WILLIAM HARBORD, Analytical Chemist, Surbiton House, Englefield
Green, in the County of Surrey, and GEORGE MINCHIN MINCHIN, Professor of
Mathematics, Coopers Hill College, Englefield Green in the County of Surrey,
do hereby declare the nature of this invention and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement:-
The object of our invention is to provide a non-combustible wick which, while
readily conducting the oil, shall not itself char or burn away, and consequently
the necessity for trimming is avoided.
For this purpose we use preferably the well known absorbent material kieselguhr,
so largely used as an absorbent for nitroglycerine in the manufacture of dynamite;
or in some cases we may use plaster of Paris, or Portland cement, both of which
which have good absorbent properties.

page_text: In making the wicks of kieselguhr, we prefer to mix the kieselguhr with a
small quantity of very finely ground Portland, Roman, or similar, cement, to
insure, on drying, greater hardness; and the exact proportion is not of any great
importance, as good results can be obtained with mixtures varying from 5%
to 20% of the cement; and we prefer to use as small a proportion as possible,
consistent with obtaining the desired degree of hardness.
The wicks may be
made entirely of kieselguhr & give excellent results, but the hardness is increased
by the addition of cement as described.
The finely ground kieselguhr either alone or mixed with cement is made into
a stiff paste with water & kneaded, & moulded into the shape required for the
special form of lamp, & may be flat or retangular, solid cylinders or circular tubes,
or any other desired form. They may be made hollow for better attachment of
the cotton wick, as afterwards described, or a solid plug with a large base.
Whatever the shape after moulding, they are carefully dried, & may be fired
at high temperature, but this latter is not absolutely essential except when no
cement is used.
Instead of using Portland or similiar cement, the kieselguhr may be moulded
with a solution of silicate of soda (about 5% to 10% solution), or a solution of
nitrate of soda or potash, borax, or other similar material capable of combining
with the silica of the kieselguhr to form a silicate of the alkali in situ & so
frit the mass together when fired at a high temperature. Instead of using a
solution of nitrate of soda or potash a small quantity-say equal to 5 per cent.-
of nitrate of potash, soda, or borax may, in the dry state, be intimately mixed
with kieselguhr, and the whole moistened with water in sufficient quantity to
form a stiff paste for moulding. After moulding, the wicks, of whatever shape,
are carefully dried & kilned at high temperature.
It may be advisable, in order to give mechanical strength to the moulded wick,
to coat it with a thin layer of hard setting fire clay or cement to within about
of an inch of the top where it is contact with the flame, & to carry little
ribs of this outer coating to the top edge of the wick.
In making the wicks of plaster of Paris, or of Portland or similar cement,
the material in each case is moistened with water & moulded to the required form,
& allowed to dry.
When made of plaster of Paris, it may be advisable to give mechanical strength
by an outside coating of hardsetting clay or cement, as described, for the
kieselguhr wicks.,
In all cases, whether the wicks are moulded of kieselguhr, plaster of Paris,
or cement, or a mixture of kieselguhr & cement, as above described, if desirable
capillary holes or channels may be formed in the body of the wicks either during
moulding by embedding fine threads or fibres capable of being afterwards burnt
out, or by piercing holes by any suitable machine after moulding; or these fine
holes may be formed by any other convenient means.
.
In cases where the burner of the lamp is raised a considerable distance above
the oil reservoir, the oil may be conducted to the incombustible wicks by means
of cotton wick, cotton wool, sponge, or other suitable material, which is kept
in intimate contact with the incombustible wick by means of pressure, or embed-
ding the cotton wick, or by firmly attaching it by any suitable means.
In cases where the burner & the reservoir are close together, as in bicycle lamps,
the cotton conductor may be dispensed with, & the noncombustible wick may dip
directly into the oil.
Having now hereby declared & ascertained the particular nature of our said
invention and the manner in which the same is to be performed, we hereby
declare that what we claim is:-
(1) The manufacture and use of incombustible wicks made of kieselguhr either
alone or of kieselguhr mixed with any suitable proportion of Portland, Roman,
or other similar cement, as above described.

page_text: (2) The manufacture and use of wicks made of kieselguhr moulded with a
solution of silicate of soda, as above described.
(3) The manufacture of kieselguhr wicks moulded with a solution, or intimately
mixed with a small quantity of dry nitrate of soda or potash, or with borax,
or any suitable fusible material capable of combining with the silica in the
kieselguhr to form a binding material in situ, as described.
(4) The manufacture and use of wicks made from plaster of Paris, as above
described.
(5) The manufacture and use of wicks made from Portland, Roman, or similar,
cement, as above described.
(6) The coating of the above incombustible wicks with a thin case of any
suitable cementing 'material to mechanically strengthen the wick, as above
described.
(7) The manufacture and use of the above wicks, either with or without
capillary channels or passages, as above described.
(8) The use of any of the above wicks either alone or in combination with
cotton wick, cotton wool, sponge, or any other suitable material, to act as a
conductor of the oil from the reservoir to the incombustible wick, such conducting
material to be kept in contact with the said incombustible wicks by any suitable
means.
(9) The use of kieselguhr either alone or mixed with any other material for
the manufacture of wicks substantially as described.
Dated this 3rd day of December 1898.
F. W. HARBORD,
GEORGE M. MINCHIN.