IMPROVEMENTS IN BULLS-EYE LANTERNS.
Year: 1877

page_text: LETTERS PATENT to John Knight Stead, of the Firm of J. Knight Stead and
Company, of the City of London, for the Invention of "IMPROVEMENTS IN
BULLS-EYE LANTERNS.
"
Sealed the 22nd June 1877, and dated the 16th March 1877.
PROVISIONAL SPECIFICATION left by the said John Knight Stead at the
Office of the Commissioners of Patents on the 16th March 1877.
JOHN KNIGHT STEAD, of the Firm of J. Knight Stead and Company, of the City
of London. "IMPROVEMENTS IN BULLS-EYE LANTERNS."
This Invention relates to hand lanterns known as bull's-eye or dark lanterns,
such as are inade use of by policemen, letter carriers, and others, the object being to
readily render the lantern "dark" or "light" by means of an instantaneous appli-
cation of the thumb upon a latch piece instead of by the old way of turning the
inner chamber of the lantern half round.
In carrying out the Invention the lantern body is constructed of required form
with bull's-eye, lamp part, air chamber, and handles of substantially the ordinary
form. To the back part of the lantern body above the handle is hinged a
Jatch or thumb piece working in connection with a spring finger, said spring
finger having on the extremity thereof a vee-shaped inetal lump working in
connection with the latch or thumb piece above described, so as to retain said latch
or thumb piece in its raised or depressed position after having been acted upon by
the thumb of the user. To the hinged end of the thumb piece is attached or formed
of a piece therewith a metal lever, which lever extends through a hole or perforation
in the lantern case, and then divides out into two curved arms extending around
the inside of the light chamber, and terminating in a nose piece, whereon is hung a
hood or screen of metal so as to be operated through the latch or thumb piece and
lever to cover or uncover the bull's-eye, and so render the lantern "dark" or
"light." The said screen has its two sides bent, and these bent sides take into two
perpendicular guides within the lantern case, and work therein to steady the screen
when it is raised or lowered through the lever; and said lever is preferably made of
bent steel wire, in which case the wire also forms the foundation of the thumb
piece.

page_text: In this class of lantern as heretofore constructed the use of both hands is required
to turn it from "dark" to "light," and vice versa; but according to my improved
system the change from "dark" to "light" can be effected instantaneously by a
movement of the thumb of the same hand in which the lantern is held.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Knight Stead in the Great Seal Patent Office on the 15th
September 1877.
JOHN KNIGHT STEAD, of the Firm of J. Knight Stead and Company, of the City
of London. "IMPROVEMENTS IN BULL'S-EYE LANTERNS."
This Invention relates to hand lanterns known as "bull's-eye" or dark lanterns,
such as are made use of by policemen, letter carriers, and others, the object being to
readily render the lantern "dark" or "light" by means of an instantaneous application
of the thumb upon a latch piece instead of by the old way of turning the inner
chamber of the lantern half around.
And in order that the said Invention may be well understood, I shall now
proceed to more particularly describe the same, reference being made to the accom-
panying Drawing, like letters of reference indicating corresponding parts in all the
Figures:.
Fig. 1 is a sectional elevation of my improved bull's eye lantern; and Fig. 2, a
plan of the same with ventilating top removed.
A represents the outer case of the lantern carrying the bull's-eye B; C, the oil
and wick holder; D, air chamber; and E, handles, all being substantially the same
as in ordinary lanterns. To the back part of the inner case or light chamber F of
the lantern, above the handles E, is hinged a latch or thumb piece G, working over
or in connection with a spring finger H, secured in a convenient position at the top
of the air chamber D, and formed at its back part near its extremity with a V or
cam shaped metal lump I, working in connection with the latch or thumb piece G
so as to retain the latter in a depressed or raised position after being acted upon by
the thumb of the user, as hereafter described. To the hinged portion of the latch
or thumb piece G is attached (or formed of a piece therewith) a metal lever J which
extends through a hole or perforation & in the inner case or light chamber F, and
then divides out into two curved arms extending round the inside of the inner case
or light chamber F, and terininating in a nose piece y, whereon is hung a hood or
metal screen K, the sides or edges of which are bent so as to take into two per-
pendicular guides L, L, within the inner case or light chamber F, and slide therein
for the purpose of steadying and guiding the hood or screen K when raised or
lowered by the lever J; this lever is preferably made of bent steel wire, in which
case the wire also forms the foundation of the latch or thumb piece G.
According to the above arrangement, by pressing the thumb on the latch or
thumb piece G and depressing the same, the lever J and with it the hood or screen K
are raised (as shown in dotted lines, Fig. 1), and the latter thereby uncovers the
bull's-eye B or renders the lantern "light," the hinged portion of the lever J which
carries the latch or thumb piecc G at the same time passing over the V or cam-
shaped metal lump I on the spring finger H locks or retains the hood or screen K
in the raised position until desired to turn the lantern dark, when the latch or
thumb piece G is raised by the thumb, and the lever J being thereby lowered, carries
with it the hood or screen K, which covers the bull's-eye B or turns it "dark."
In ordinary bulls-eyo lanterns the use of both hands is required to turn it
from light to dark, and vice versa, but by this Invention the change from
light to dark can be effected simultaneously by a movement of the thumb of
the same hand in which the lantern is held, this being an advantage of great
importance to policemen in case of assault or otherwise, or when used by watchmen,
or for railway or other purposes.

page_text: Having now described the nature of my said Invention 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 novel and therefor claim as the Invention secured to me by the
herein-before in part recited Letters Patent is, the improvements in bull's-eye
lanterns, substantially as and for the purposes herein-before described and illustrated
by the accompanying Drawing.
In witness whereof, I, the said John Knight Stead, have hereunto set my hand
and seal, this Fourteenth day of September, One thousand eight hundred
and seventy-seven.
J. K. STEAD. (L.S.)