IMPROVEMENTS IN THE MODERATOR LAMP, OD IN LANDS OF AGIMILAR PRINCIPLE."
Year: 1853

page_text: LETTERS PATENT to Samuel Sedgwick and Thomas Dawson, of 186,
Piccadilly, for the Invention of "IMPROVEMENTS IN THE MODERATOR LAMP,
OD IN LANDS OF AGIMILAR PRINCIPLE."
PROVISIONAL SPECIFICATION left by the said Samuel Sedgwick and
Thomas Dawson at the Office of the Commissioners of Patents, with their
Petition, on the 27th December 1853.
We, SAMUEL SEDGWICK and THOMAS DAWSON, of 186, Piccadilly, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE MODERATOR
LAMP, OR IN LAMPS OF A SIMILAR PRINCIPLE," to be as follows:-
These improvements have reference to that description of lamps known as
the "moderator," or to lamps of a similar principle. The principle of the
moderator lamp is that of regulating the supply of oil by mechanical pressure,
either by a spring and plunger or by clockwork, the oil being forced upwards
to the cotton, which, by capillary attraction, retains the oil. And our improve-
ments consist,
First, of the use of a circular piece of perforated metal, such as zinc, which
we call a metallic air regulator. This is placed on the shoulder of the lamp
and surrounds the stem; the object of this is to regulate the supply of atmo-
spheric air for combustion. It may or may not be fixed to the outer shoulder
or stem of the lamp.

page_text: Secondly, our improvements consist of the use of apertures in the top of the
shaft of the lamp to admit of the escape or overflow of oil, thus checking the
entire saturation of the cotton, which prevents its lighting.
Thirdly, our improvements consist of the use of a glass or metallic, or glass
and metallic "cone," placed around the shaft of the lamp, for the
concentrating the atmospheric air for combustion.
purpose of
Fourthly, our improvements consist of the use of a contracted chimney in
such lamps, that is to say, the glass chimney is so made as to form a cone,
answering the same purpose as the separate cone before described. This
contracted chimney may be used with or without the cone.
Fifthly, our improvements consist of the use of a circular piece of metal
placed in the glass chimney of the lamp where it is contracted, or where the
shoulder usually is, for the purpose of deflecting and concentrating the air.
We do not confine ourselves to the precise details as herein set forth, but,
substantially, the above is a description of the principle features of our
improvements, which are only claimed by us when applied to lamps made on
the moderator principle.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Samuel Sedgwick and Thomas Dawson in the Great Seal
Patent Office on the 27th June 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, SAMUEL
SEDGWICK and THOMAS DAWSON, of 186, Piccadilly, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of December, in the year
Lord One thousand eight hundred and fifty-three, in the seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto us,
the said Samuel Sedgwick and Thomas Dawson, Her special licence that we,
the said Samuel Sedgwick and Thomas Dawson, our executors, administrators,
and assigns, or such others as we, the said Samuel Sedgwick and Thomas
Dawson, our executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE
MODERATOR LAMP, OR IN LAMPS OF A SIMILAR PRINCIPLE," upon the condition
(amongst others) that we, the said Samuel Sedgwick and Thomas Dawson, or

page_text: one of us, by an instrument in writing under our hands and seals, or under
the hand and seal of one of us, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be per-
formed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Thomas Dawson, for myself and the
said Samuel Sedgwick, do hereby declare the nature of our said Invention, and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
Our Invention has reference to improvements in lamps of the description
known as the moderator, or in lamps of a similar construction. The principle
of the moderator lamp, as is well known, is that of regulating the supply of oil
to the wick by forcing it upward by means of a piston or plunger, which rests
upon the surface of the oil in the reservoir. A spiral spring fastened to the
upper part of the reservoir presses on the piston or plunger which it forces
downward, causing the oil to ascend the tubes, by which it is conveyed to the
wick.
The first part of our improvements consists in the use of a cylinder of
perforated metal, which wo term an air regulator; this is fitted within the
outer ornamental shaft or gallery which supports the glass holder. The object
of this arrangement is to increase and regulate the supply of air for the
combustion of the oil. The perforated cylinder may or may not be fixed to the
shoulder or stem of the lamp.
Secondly, our improvements consist of the use of a glass or metallic, or of a
glass and metallic "cone," placed on the glass holder, and surrounding the
flame in such manner as to cause the outer current of air to impinge on the
flame, thereby increasing its intensity.
Thirdly, our improvements consist of the use of a contracted chimney with
moderator lamps or others of similar principle; that is to say, the glass
chimney is so made as to form a cone answering the same purpose as the cone
before referred to; this contracted chimney may be used with or without the
"cone." In lieu of the moveable cone a fixed metallic or glass and metal cone
may be attached to the glass holder or chimney support.
Fourthly, our improvements consists of the use of a circular piece of metal
placed within the glass chimney of the lamp where it is contracted, or where
the shoulder usually is, for the purpose of deflecting the current of air upon
the flame.

page_text: But in order that our Invention may be fully understood we will proceed to
describe the various parts in detail, referring to the accompanying Drawings,
and to the letters and figures marked thereon.
.
Fig. 1 is an elevation of the upper part of a moderator lamp, showing our
improvements applied thereto. Fig. 2 is an elevation, with the chimney and
outer ornamental shaft removed, so as to show the position of the air regulator.
Fig. 3 is an elevation, with the air regulator removed, to show our improve-
ments in fitting the rack and pinion for elevating the piston or plunger; Fig. 4
is a plan of Fig. 3. Fig. 5, a section of the glass holder and outer shaft.
Fig. 6 is a plan of the glass holder. Fig. 7, a side elevation of the air regulator.
Fig. 8, an elevation of the glass chimney, shown in Fig. 1. Fig. 9, an elevation
and plan of the conc; and Fig. 10, an elevation of a chimney for supporting a
metallic ring within the contracted part, which answers the purpose of the
cone, Fig. 9. A, Fig. 1, is the upper part of the reservoir or space for con-
taining the oil to be consumed; B is a brass or other metal cylinder or shaft,
perforated at C for the admission of air to the flame; this shaft or cylinder
forms the upper external portion of the lanp, and may be lacquered, plated, or
>therwise ornamented, as desired; the lower part rests on a ledge at D, made
within the shoulder of the lamp. The cylinder B is firmly held in its place by
the glass holder E, which fits on the wick holder, and within the cylinder B;
the arrangement is more clearly shown by Figs. 5 and 6. Fig. 5 is a vertical
section of the glass holder and cylinder; Fig. 6 is a plan of the chimney holder.
F is a short cylinder of tinned iron or other suitable metal; this is made to fit
tightly on the wick holder G, upon which it is placed, and pushed down; the
flange H fits within the cylinder B, and retains it firmly in its place. The
upper edge of the cylinder F is cut of an angular shape, and the metal turned
outward. At the lowest side of the cylinder a small passage or channel 1 is
made. When the glass holder is in its place, the surplus or unconsumed oil, as
it flows over the wick holder G, is caught by the gutter or channel formed by
the edge of the cylinder F, and flows through the passage I, back to the
reservoir. K, K, are arms which support the cylinder F; L is the gallery in
which the glass chimney is placed; M, Fig. 1, is the "cone," which rests on
the arms. K, K, of the glass holder, or it may, if preferred, be fastened thereto.
The cone is a short cylinder of glass, the upper part of which is contracted, as
shown. A metal ring N is fitted into the aperture of the contracted part; the
diameter of the metal ring should correspond, or nearly so, with the wick-
holder G. The cone is shown separately by Fig. 9. O; Figs. 1 and 8, is the
glass chimney, which is sharply contracted at the part O', forming an abrupt

page_text: shoulder; this causes a rapid draught of air to pass through it, which is
brought into close contact with the flame at the narrow part, thereby increasing
its intensity and augmenting the amount of the diffused light. The air
regulator P is a cylinder of perforated zinc or other suitable metal, shown
separately by Fig. 7, and in the position it occupies within the cylinder B, by
Fig. 2. On the wick holder G is a flange or collar Q, the upper surface of
which is inclined, and at the lowest part has a small lip or spout, which convey's
away the surplus oil as it drops from the cylinder F of the glass holder E. The
air regulator P is made to fit over the flange Q, and of a height corresponding
with it, the upper edge being cut to a similar angle, as shown by Fig. 7; a slot
is cut in each of its sides, to allow it to pass over the spindles of the wick and
piston pinions. The lamp may be used without the air regulator, but its use
prevents any sudden currents of air disturbing the flame and thereby causing it
to flicker. Fig. 3 is an elevation, and Fig. 4 a plan (drawn full size), showing
our improvement in fitting the rack and pinion which actuates the piston or
plunger. R, R, are tubes through which the oil is forced to the wick; S is a
brass bearing, a notch or recess in which serves to hold and guide the rack 'T';
U is the pinion, the spindle of which is supported at one end by the bearing S,
the other passes through the piece of tubing U'; V is the handle of the pinion
for elevating the piston; W is a milled head on the spindle of the pinion,
which raises or depresses a spring clip within the wick-holder G for raising the
wick as it is consumed. Fig. 10 represents a chimney to be used in lieu of
the cone, Fig. 9. This chimney is contracted at the part marked æ, and on
this inner projecting part is placed a metal ring, the inner diameter of which
corresponds, or nearly so, with the wick; this arrangement serves to deflect
the air, causing it to impinge on the flame, similar to the action of the cone, as
herein-before described in reference to Figs. 1 and 8.
Having described the nature of our Invention, and the manner of carrying
the same into effect, we wish it to be understood that we make no claim to
the several improvements herein-before described, taken separately and apart
from their application to the particular description of lamp known as the
"moderator," or others of a similar principle; nor do we confine ourselves
to the precise details of arrangement as herein described and shewn. But
what we claim, and desire to secure by the herein-before recited Letters
Patent, is,
Firstly, the construction and arrangement of the perforated outer cylinder
and glass holder, as described and shown.
Secondly, the construction and arrangement of the air regulator and mode of

page_text: fitting the mechanism for raising the piston or plunger in the centre of the
space between the oil tubes, as described and shown.
Thirdly, the application of the "cone," or any substitute therefor, to
moderator lamps, and the contracted glass chimnies, used either with or
without a metallic ring, as described and shown.
In witness whereof, I, the said Thomas Dawson, have hereunto set my
hand and seal, the Twenty-seventh day of June, in the year of our
Lord One thousand eight hundred and fifty-four.
THOMAS DAWSON. (L.S.)