IMPROVEMENT IN LAMPS
Year: 1875

page_text: LETTERS PATENT to George Henry Lomax, of the State of Massa-
chusetts, of the United States of America, for the Invention of
"IMPROVEMENT IN LAMPS."
Sealed the 25th June 1875, and dated the 3rd May 1875.
COMPLETE SPECIFICATION filed by the said George Henry Lomax at
the Office of the Commissioners of Patents, with his Petition and
Declaration, on the 3rd May 1875, pursuant to the 9th Section of
the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HENRY LOMAX, of the State of Massachusetts, of the United States of
America, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENT IN
LAMPS," and have petitioned Her most Excellent Majesty Queen Victoria
to grant unto me, my executors, administrators, and assigns, Her
Royal Letters Patent for the same, and have made solemn Declaration
that I am the first and true Inventor thereof.

page_text: NOW KNOW YE, that I, the said George Henry Lomax, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawings and to the letters and figures marked thereon (that is to
say):
In such Drawing Figure 1 is a parti-sectional elevation of a lamp.
containing my improvement; Figure 2 is a section of a part of the lamp
as it comes from the mold.
It is well known that the contents of kerosene lamps so called
frequently overflow from several causes, one being that the lamp is filled
too full originally, another that the expansion of the contents after
filling ensues by subjection to a subsequent warmer atmosphere ōr
locality, and another is the capillary attraction of the wick, the fluid in
all these instances flowing over the exterior of the lamp with the
disagreeable consequences now so constantly experienced.
The purpose of my Invention is to arrest this flowage of fluid over the
exterior of the lamp, and to this end I form or erect upon the upper part
of the same or the oil reservoir thereof a raised lip or rim, which shall
circumscribe its burner or filling orifice, and which by its presence shall
check and retain in a small space any excess of oil or fluid which may
find its way outside of said burner or orifice, and from whence it may be
expeditiously and easily wiped or removed without contact with any
extended portion of the outside area of the lamp.
The Drawing annexed to this Specification represents at A. a lamp of
which a is the base or standard; b, the oil reservoir; and c, the filling
orifice; such component parts constituting a lamp of ordinary manu-
facture.
In carrying out the purposes of my Invention as prefaced in this
context, I form upon the upper part of the oil reservoir or bowl ba
rising rim or ledge d, this rim circumscribing the filling orifice c, and
being of such diameter and height as to retain any amount of oil which
would under any circumstances overflow from the reservoir.
I have found by careful experiments that the ledge or rim before
spoken of serves to retard or interrupt to a great and desirable extent
escape of oil from the reservoir by capillary or other attraction.

page_text: "
Another advantage of the presence of the annular circumscribing rim
is, that it affords a broad and steady support for a shade," as the base
or feet of the frame of such shade may rest directly upon it without
connection with the burner.
I am aware of the existence of the Invention exhibited in Letters
Patent of the United States, No. 40, 094, and dated September 29, 1863,
in which a concentric groove or depression is formed in the upper part
of the bowl of the lamp and surrounding its cap, such lamp being of the
class known as blow-over" lamps, or those in which the glass is dis-
tended and forced into the depressions and concavities of the mold by
the action of air usually from the lungs of the workman.
"
66
My present Invention as above explained relates to a lamp of entirely
different character from the above, so far as its mode of manufacture is
concerned, since it is produced in a pressure mold," so called, in which
the glass in a soft state is driven into the irregularities of the mold by
means of a metallic plunger in a powerful press. The distinction
between these two modes of producing glass-ware consists in this, that in
the blow-over system the glass can only be forced into very shallow
depressions or concavities, as it will cling to the edges of such con-
cavities and be either reduced to an injurious thinness or be entirely
broken off. In the present mold system on the contrary, the glass
owing to the unyielding nature of the plunger which drives it, may be
forced into very attenuated recesses or irregularities of the mold as all
glass workers will understand.
In producing the annular lip or wall which constitutes my present
Invention, the glass shell which constitutes the lamp makes its exit from
the mold in the form shown in Figure 2 of the accompanying Drawing,
since this form is the most economical one in which to produce it. The
shell thus formed is subsequently manipulated into a complete lamp
body by bending the upper part of the cylinder A' inward, this act
tilting the lip or wall into the inclined position shown in dotted lines in
Figure 2 of the Drawing. My invention will thus be seen to have
especial reference to "pressed" articles of glass-ware, since it cannot be
produced in blow-over molds, consequently I claim as my Invention the
following:-
As an improved article of manufacture a pressed glass lamp provided
-

page_text: orifice or burner thereof in manner and for the purpose herein-before
explained.
In witness whereof, I, the said George Henry Lomax, have here-
unto set my hand and seal, this 20th day of April, 1875.
GEORGE HENRY LOMAX. (L.S.)