IMPROVEMENTS IN LAMPS
Year: 1878

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN
LAMPS." A communication from abroad by Robert Hitchcock, of Watertown,
in the County of Jefferson, State of New York, United States of America.
COMPLETE SPECIFICATION filed by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 24th July 1878.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN LAMPS." A communication from abroad by Robert
Hitchcock, of Watertown, in the County of Jefferson, State of New York, United
States of America.
-
This Invention relates more particularly to what are known as ship-standing
lights or box lamps, which of necessity are exposed to the weather, but is also appli-
cable to other descriptions of lamps.
In view of the important purpose which ships' lamps subserve, and the danger
consequent on their being accidentally extinguished or failure to shed their light
properly, the production of a ship lamp which, although subjected to blasts of wind
and rain, or to the rolling and pitching of the vessel, shall give a steady, unflickering,
and constant light has been a matter much desired and sought for by those interested
in the transportation by water of merchandise and passengers.
The lamps of this class heretofore made have failed more or less signally in accom-
plishing the end sought; either the light does not burn clear and bright, or it is
liable to be made to flicker and go out by reason of the penetration of blasts of air
thereto, or by the rolling and pitching of the vessel.
The object of this Invention is essentially the production of a ship lamp which
shall possess in a very perfect manner these advantages, and it consists of an
improved combination and construction of parts for supplying and regulating the
air to the burner, for receiving the air into the lamp case, and discharging from the

page_text: case the products of combustion; in the construction of the wick tube or burner,
and the air passages connected therewith; in the construction and combination of
parts for preventing danger of overheating the oil in the tank by the lamp flame,
while maintaining compactness of structure; and in the combination with the oil
tank of means to maintain the steadiness of the light.
And in order that the said Invention may be fully understood I shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the annexed Sheet of Drawings, the same letters of reference
indicating corresponding parts in all the Figures.
Figure 1 of the Drawings represents a perspective view of a lamp .constructed
according to this Invention; and Figures 2 and 3 are vertical sections taken at
right angles to each other.
The lamp case is provided with glass secured in suitable frames on three sides,
and with a reflector secured at the back.
A represents the top of the case; B, the back; C, the bottom; and D, uprights or
standards at the corners connecting the top and bottom, and to which the frames of
the glass are secured, one of the frames being hinged, as shown at 1, 1, to serve as a
door.
The top, bottom, back, and uprights are all made hollow, and form a series of
intercommunicating air chambers, as is clearly shewn in the various Figures. In
Figure 2 portion of the wall of one of the uprights is broken away for the purpose
of more clearly showing that it is hollow.
E, E', represent concentric exterior and interior cylinders, the former being fora-
minous, and the two forming flanges to an annular chamber between. F, F¹, repre-
sent two caps; the top cap F' is elevated sufficiently above the lower one F to
form an annular space between them, and its edges extend beyond the edges of the
opening formed in the lower cap; it is constructed, as shewn in Figures 2 and 3, of
two plates f, f, united at their edges, and provided with perforations 2.
G represents the oil tank, provided with a cylindrical opening 3 in the centre,
and connected by means of pipes G¹ with an elliptical wick tube or burner H placed
in the opening. The wick tube is surrounded by a cylindrical tube K, made flaring
at the bottom, and supporting a deflector I at its upper end; it is connected with
the oil tank by suitable braces, so as to form passages on both sides between itself
and the wick tube H, and the walls of the cylindrical opening 3 in the oil tank:
Vents or air admission tubes L are connected with the oil tank, which serve to
readily admit air into the tank or to allow it to escape therefrom, and by the aid
of a screw connection they may be used as stoppers to be removed for filling the
tank.
M represents the reflector at the back of the case, removably attached to the inner
wall thereof. a, a¹, represent the outer and inner walls of the top; b, b', the walls of
the back; and c, c', represent respectively the exterior wall and the top of the hollow
battom; this top or partition e' has a circular opening. therein, and surrounded by a
flange c. The wick tube H and the tube K. pass through this opening into the air
chamber of the bottom C. A circular flange g depends from the oil tank, and fits
within the flange c², so as to prevent passage of air between them. These flanges
also. serve, in combination with strips, g₁ secured on the lower side of the oil tank, to
hold the oil tank steady in position.
From the foregoing description it will be perceived that when the door is shut.
the lamp is closed to the external air on all sides except at the top, where it may
pass into and out of the case through the perforations in the foraminous cylinder E,
and through the annular opening between the caps F and F¹.
i
It will also be perceived that the escape from the interior of the case of the pro-
ducts of combustion from the burner is through the internal cylinder E', and thence
naturally through the annular opening between the caps and the perforations 2 in
the upper cap fl
The air chamber or passages in the top, back, and tubular uprights of the case
carry the air drawn in through the perforations in the cylinder E into the chamber.

page_text: in the bottom C, whence it passes to the burner through the interior of the elliptical
wick tube, and through the space between the outside of the wick tube and the
surrounding tube K, the deflector I serving to direct the air into contact with the
flame of the lamp. The annular opening between the tube K and the wall of the
oil tank also serves as a passage for air, the current of which, passing therethrough
serves to keep the oil in the tank cool, and prevent danger arising from the over-
heating thereof by the lamp flame.
The lamp thus being entirely excluded from the direct or indirect action of blasts
of air, while at the same time a liberal supply is furnished for the purposes of com-
bustion, will burn with a clear steady flame, without flickering or liability of being
suddenly extinguished.
The due supply of air to the burner is assisted by the elliptical form of the wick
tube, as the current of air passing through the interior thereof is brought wholly
into contact with the flame, and not the outer layer only, as in round burners;
and also the broad flame produced thereby is more suitable for the desired illumi-
nation.
The liability of the oil tank to become too hot being avoided, as above explained,
mineral oils may be used in the lamps without danger; and by the provision of the
air vents or admission tubes to the oil tank, the steadiness of the light is main-
tained, as the flow of the oil to the wick tube is regular, and the oil is not liable to
be thrown thereout by the rolling and pitching of the vessel, on account of the
length and shape of the tubes.
It will be obvious that a round wick tube, or wick tubes of other than elliptical
form, may be used with the tube surrounding it, and located within the cylindrical
opening in the oil tank, and also in connection with the construction of the lamp
case, as described, but not with so good an effect.
Having now described and particularly ascertained the nature of the said Inven-
tion, and the manner in which the same is or may be used or carried into effect,
I would observe in conclusion that what I consider to be novel and original, and
therefore claim as the Invention is,―
1st. A ship standing lamp or ship box lamp in which all the parts, with the
exception of the glass panes and their frames, are communicating air chambers
receiving all the air for the supply of the lamp from without, and discharging the
products of combustion through the top, substantially as herein-before described.
2nd. The combination in-a lamp case or box of a double roof, a double.back, a
double bottom, and tubular uprights uniting the roof and bottom, all constituting
air-tight intercommunicating chambers, as herein-before described.
3rd. The combination with the double and internally communicating top and
bottom and uprights of a ship lamp, of a top consisting of an exterior and interior
cylinder, the former of which is foraminous, the two forming flanges to the annular
opening of the air chamber, the said top being surmounted by two caps having an
annular opening between them, the upper being a chamber provided with openings,
the whole constructed and arranged substantially as herein-before described, and
illustrated by the Drawings.
4th. In ship or other lamps for burning heavy or light oils, fat, or other illumi-
nating material, the combination of an elliptical burner and a hollow box or case
surrounding the same, through parts of which hollow box is conveyed all the
air used for the combustion, substantially as herein-before described, and illustrated
by the Drawings.
5th. The combination in a ship or other lamp of a burner of a cylindrical or
elliptical form of wick tube and a jacket or cylinder surrounding the wick tube
and extending below the tank, the cylinder being provided with the deflector, sub-
stantially as herein-before described, and illustrated by my Drawings.
6th. In a lamp for ship or other uses, the burner communicating with an air
chamber and oil tank, so arranged that the air shall be caused to pass both through
and around the burner between it and the tank, substantially as and for the purposes
herein-before described.

page_text: 7th. In ship lamps, the combination with the tank of air vents or air admission
tubes, which may or may not serve the purpose of stoppers, substantially as herein-
before described.
In witness whereof, I, the said John Henry Johnson, to this my Complete
Specification set my hand and seal, the Twenty-fourth day of July, One
thousand eight hundred and seventy-eight.
J. HENRY JOHNSON. (LS)