Improvements in Oil Lamps.
Year: 1898

page_text: Date of Application, 17th Mar., 1898-Accepted, 3rd Dec., 1893
Improvements in Oil Lamps.
I CHARLES LANCASTER MARSHALL, a citizen of the United States, residing at
Cedar Grove, in the County of Essex and State of New Jersey, Manufacturer, 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:
In the incandescent oil lamp about to be put on the market, the great objection
is the unreliability and unsteadiness of the wick in its oil carrying power. When
the wick is properly adjusted to its lamp it will behave all right for a few hours,
perhaps twenty four or thereabouts, depending upon the particular wick. Then
the wick begins to show its loss of capillary power and its clogging by a reduction
in the amount of oil carried to the flame which then smokes, depositing carbon on
the mantle and destroying its illuminating power and sometimes causing accidents.
The lamp as at present proposed with the ordinary cotton wick of commerce is
therefore a commercially useless device.
The object of my invention is to substitute in the incandescent lamp a wick that
is not open to these objections. One of the reasons why the ordinary cotton wick
clogs is its ability to hold water in suspension, thus preventing the passage of oil.
This is perhaps the main difficulty.
In order to produce a successful wick, it is necessary to prevent it from holding
water in suspension, and to choke and regulate its carrying capacity. To secure
this result I have reduced and choked the carrying capacity of the wick patented
to me by the addition of starch.
In Figure 1 is shown a sectional view of the incandescent burner.
In Figure 2 is shown one form of my wick reduced in size.
In Figure 3 is shown a preferred form of my wick in section.
Figure 4 is a plan view of the bottom of the cylinder which carries the wick.
The lamp consists in a body or framework 1, having screw threads 2, by which
the framework is fastened to the oil tank (not shown). Within the framework
is the cylinder 3, mounted rigidly on the webbing 4. This cylinder confines part
of the wick on the outside. Upon the top of this cylinder is a smaller cylindrical
section 5, fastened by a bayonet joint 6 shown in Figure 1. The function of this
smaller, cylindrical section is to surround the top of the wick on the outside.
Within and concentric with these cylinders is a second cylinder 7, which is
provided with a slot 8, registering with a slot 9 in the cylinder 3.
The two cylinders 3 and 7 are firmly connected together by a web 10, around
the outside of the two slots as shown. Thus an air passage is provided from the
outside of cylinder to the inside of cylinder 7 and is shut off from the space
between the cylinders which is reserved for the wick 24.
Within and concentric with the second cylinder 7 is a tube 11, preferably
rectangular so as to fit a rack 12, adapted to slide up and down within the tube.
The upper end of the tube is held in place within the cylinder 7 by three posts 13,
and the lower end is held in place by the two discs 14, forming a chamber

page_text: between them. Within this chamber this tube is cut away to allow a pinion 15
to operate the rack up and down to adjust the wick. The pinion 15 is mounted
upon an arbor 16, turning in the tube 17, and is worked by a handle 18. The
tube 17 is rigidly mounted upon the framework as shown.
The rack 12 at its lower end is provided with a firmly mounted disc 19, and
screw threads 20. Smoothly sliding on the outside of the cylinder 7 is a third
cylinder 21, having a slot 22, which allows for the web 10, between the first
and second cylinders. The cylinder 21 has sharp points 23 at its top to press into
the wick 24 and carry the wick up and down whenever the cylinder 21 is moved.
The cylinder 21 is removably connected with the rack 12. The cylinder end
is mounted rigidly in the cap 25 which has the slot 26. The cross piece 27,
with wings 28 to turn it with is pivoted on the screw threads 20, passed through
the slot 26, and turned at right angles with the slot so that it abuts against the
offset lug 29. It is held there from dropping off the screw threads by the nut 30.
In this way the cylinder 21 and rack 12 are so connected that when the pinion 15
is turned by the handle 18, the rack 12 causes the cylinder 21 and the wick 24
carried thereby to move with it. In this way the wick is adjusted for the best flame.
In the top of the tube 11, which is cylindrical above the range of the rack,
is removably mounted a post with a limiting shoulder 32 to prevent its going
down too far. Upon this post is rigidly mounted the gasifyer, a chamber 33,
with apertures 34.
Upon the circular groove 35, rests the chimney and mantle support 36. This
support has the main cylindrical portion 37 with three top cylindrical parts 38,
39, 40, the latter two provided with air holes.
Upon the framework 1 is mounted rigidly at both ends a screw 53, upon which
a thumb nut 54 works and raises the support 36 off the groove by means of the
shoulder 55. This is to adjust the mantle to the flame as regards position.
The outer cylindrical portion 40 has lugs 41, three or four in number, to
support the chimney 48.
The middle cylindrical portion 39 is to fit inside the bottom of the mantle 42
and steady it in its position. The inner portion 38 assists in forming air passages.
Mounted upon the main cylindrical portion 37 of the support is a block of metal
with two holes at right angles to each other, a hole 44 to support the mantle
holding rod 45, and another hole 46 threaded for the set screw 47, which holds the
mantle rod ir. its position as adjusted. The upper parts of the chimney, mantle,
and mantle rod are broken away in the drawing. They are similar to the same
elements in the Welsbach gas burner.
Figure 2 shows one form of my wick. The blank space 49 upon the threads 50
shows where the starch has been applied.
In Figure 3 is the preferable form of my wick in sectional view. The parts 51,
and 52 are where the starch has been applied. The starch at 51 is to give a
smooth top edge to the wick which assists an even flame and prevents a projecting
thread from causing the lamp to smoke.
The starch at 52 is to choke and thus regulate the flow of oil. In this wick,
the starch does not go through the wick entirely, but only partially through. It
may if necessary go entirely through, or be only applied on the surface, according
to the necessary adjustment of the particular make of wicks to the particular
make of lamps. The amount of starch, the width or the depth, or place of
application are entirely dependent on the necessities of the particular case.
Although I mention starch as the particular substance used to obstruct or choke
the free passage of the oil, it is obvious that any material may be used that is
insoluble in oil used for burning at the ordinary temperature, and that will stay
in place.
In producing this wick, starch is dissolved in water and brought to the boiling
point. It is made thick and heavy. While the starch is hot the wicks, which
may be the ordinary cotton wicks of commerce, are covered or filled with starch
to the required depth and width, and then placed in an oven to bake at the

page_text: required temperature, about 400 degrees F. or thereabouts, until dry, and properly
distilled and carbonized. At this temperature twelve hours' treatment gives
excellent results. By increasing the heat and reducing the time of treatment, or
vice versa, within certain limits, similar results may be obtained. It differs from
that of my Patent of May 11, 1897, No. 582,581 in having the previous application
of starch or other insoluble matter, baked and hardened into the wick simul-
The
taneously with the distilling or with the distilling and carbonization
apparatus of the patent may be used.
The receptability of starch to water is affected by this process, so that the starch will
hold no more water than the wick. It is preferable to have the starched part of
the wick raised above the level of the oil in the tank to get its full regulating
power.
In operation, referring to Figure 1, the wick is raised just enough to light
at the top, and is left alone for a half minute or so after lighting till the flame
rises about to the top of the gasifyer, and then is raised again till the wick
nearly touches the gasifyer. When this happens the flame disappears and is
drawn into the chamber of the gasifier by the air currents, and emerges colorless
from the holes 34, whence it spreads upward on the inside of the mantle making
it incandescent.
The heat of this combustion assists in causing the oil from the wick to become
vapor thus aiding in the intensity of the heat of the colorless flame.
The air currents are several in number. The arrow 56 indicates the current
supplying the chamber of the gasifier with the air that mixes with the vapor
from the oil. The arrow 57 indicates another current which supplies more air,
some of which doubtless follows the vapor from the wick into the gasifier, and
Another air
the rest adding to the mixture which emerges from the holes 34.
current enters as indicated by the arrow 58, and assists combustion at
The various
the mantle and prevents the chimney from becoming too hot.
cylindrical parts 37, 39 and 40 of the support 36, and the framework 1 are pro-
vided with holes for these air passages.
It is clear that the wick (referring to Figure 3) may have the starch spread upon
both surfaces, or the outside surface as at 51. This is no deeper than the surface
however, leaving the threads at 50 free to hold and to carry oil. It will be
noticed that the starch at 52 is shown as extending deeper into the wick than
at 51. When the light is burning, the freedom of the threads 50 to hold oil is
not made use of, for they are drained of oil as much as possible so that the light
depends upon the oil that continues to struggle through the free space at 52.
When however the flame is extinguished, this space in the wick at 50 soon filis
with all the oil it can hold, and the space acts as a sort of reservoir for the sudden
demand of oil to heat the lamp when it is lighted again. Without this reservoir
it takes a couple of minutes to get sufficient heat for incandescent purposes, but
with this reservoir if large enough, a half minute suffices.
It is desirable to have the part of the wick below the choking portion 52 full
Otherwise the consump-
size to bring to the choked parts the full supply of oil.
tion of oil in the tank and the lowering surface will vary the carrying power of the
wick. This will cause smoking.
Trial has demonstrated that this lamp with my improved wick will burn at
one half of the cost of an ordinary oil lamp, and will give a light with a greater
illuminating power than the well known Welsbach gas burner. One filling of
oil will last several evenings. It costs about two cents for ten hours to run this
light.
It is obvious that there are many different ways in which the wick may be manu-
factured, and although I prefer the particular process described on account of
And the wick regardless
its economy I may use other processes for making it.
of the particular process used and the particular materials employed of which
there may be a great diversity lies within the scope of my invention. This wick

page_text: 18 suitable for all kinds of hydrocarbon or oil lamps or stoves which work upon the
Bunsen principle, or in which a steady but low carrying power is necessary.
"
Thus it appears that my wick rests upon two great features of value. First
the wick must have its capillary power rendered uniform, that is, it must be
steady." My wick to become steady has been distilled or carbonized either or both,
but it is obvious that any other process or treatment which secures the same result
is an equivalent. In order to be steady in its capillary power the wick must have
its ability to hold water in suspension while carrying oil to the flame destroyed.
For water is found in considerable quantities in burning oil, and if the wick will
take it up and hold it, the wick will fail to have a steady oil carrying power. After
a while it will carry less oil to the flame and the amount reduces with age. This
exists in the best wicks manufactured by other parties to-day. So that "
steady in its oil carrying capacity" is a wick that has been rendered incapable
of choking by water, and may have the various other attributes of my distilling
and carbonizing process or not as desired.
a wick
The second great feature that forms the other element of this wick is the choking
idea, so that the carrying power is adjusted to the particular lamp or burner. This
choking of the wick may be accomplished in numerous ways, and the particular
way makes no difference as far as the scope of this patent is concerned. I believe
that I am the first to discover this choking idea in a steady wick and whether
the wick is squeezed, reduced in size at particular points, or filled with some
material that is stable under the conditions of burning, makes no difference
except in the degree of success or economy. All such ideas accomplish the result
of choking with more or less success. Some substance insoluble in oil and not
injured by the distilling process I find to be preferable for this choking function.
Another feature of my invention which includes the two preceding features
is the combination of this wick with the incandescent lamp. Of course many of
the details of the structure described may be varied at will, my invention depend-
ing upon use with some means of conveying powerful heat to a substance which
becomes greatly heated and thus gives service. In the particular form of lamp
described in this case the gasifier assists in combustion and in heating the mantle
to give light. Some other form and principle of gasifier may be used, and the
mantle heated may for example be of clay or porcelain for the purpose of giving
heat in place of light. Such different forms and substances I designate as mantles
for want of a better term. And such mantles may be supported in different
ways. So that in the art of Bunsen oil burners requiring a steady oil carrying
capacity of comparatively small dimensions, this patent is in the nature of a
generic patent covering various specific patents which follow.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. In a Bunsen oil burner, a wick steady in its oil carrying capacity in com-
bination with a choking device to adjust the supply of oil through said wick.
2. In a Bunsen oil burner a wick steady in its oil carrying capacity in com-
bination with a choking substance insoluble in oil fixed in the body of said wick
for the purpose of adjusting its oil carrying capacity.
3. In an oil burner, a wick steady in its oil carrying capacity in combination
with an artificial choking device of starch to adjust the supply of oil through
said wick.
4. In an oil burner a wick steady in its oil carrying capacity in combination
with an artificial choking device of starch to adjust the supply of oil through
said wick.
5. In a Bunsen oil burner a wick steady in its oil carrying capacity having its
surface stiffened to preserve its regularity by a substance insoluble in oil and its
body choked by said substance to adjust its carrying capacity.
6. The process of manufacturing wicks which consists in filling the fibres of a

page_text: wick with choking substance insoluble in oil, and subjecting such a combination
to distillation by heat to remove all hydrocarbons and impure substances and to
bake said choking substance.
7. The process of manufacturing wicks which consists in filling the fibres of
the wicks with a choking substance insoluble in oil and subjecting such a com-
bination to distillation and carbonization by heat to remove all hydrocarbon and
impure substances and to bake said choking substance and partially carbonize
the wicks.
8. The process of manufacturing wicks which consists in filling the fibres of
wicks with dissolved starch and subjecting such a combination to distillation by
heat to remove all hydrocarbon and impure substances, and to bake said choking
substance.
9. The process of manufacturing wicks which consists in filling the fibres
of wicks with dissolved starch and subjecting such a combination to distillation
and carbonization by heat to remove all hydrocarbon and impure substances and
to bake said starch and carbonize said wicks.
10. In combination, an incandescing mantle, a gasifier, air passages, and a wick
steady in its oil carrying capacity and choked with starch.
11. In combination, a mantle, a gasifier, air passages and a wick steady in its
oil carrying capacity and adjusted to said gasifier and air passages by choking.
12. In combination, a mantle, a gasifier, air passages and a wick, steady in
its oil carrying capacity, and adjusted to said gasifier and air passages by a
choking substance insoluble in oil fixed in the body of said wick.
13. In combination, a mantle, a gasifier, air passages and a wick steady in its
oil carrying capacity and adjusted to said gasifier and air passages by a choking
substance as starch fixed in the body of said wick.
14. In combination, a gasifier, air passages, and a wick steady in its oil carrying
capacity and adjusted to said gasifier by a choking device.
15. In a Bunsen oil burner, a wick having a choking device, a space between
the choking device and the top, unchoked to act as a reservoir of oil when the
wick is unlighted, for the purpose of supplying a larger amount of oil in starting
the burner.
Dated this 31st day of January 1898.
CHARLES LANCASTER MARSHALL.