IMPROVEMENTS IN THE CONSTRUCTION OF LAMPS AND LANTERNS, AND IN LENSES EMPLOYED THEREWITH
Year: 1868

page_text: LETTERS PATENT to William Harvie, of Glasgow, in the County of
Lanark, North Britain, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF LAMPS AND LANTERNS, AND IN LENSES EMPLOYED
THEREWITH."
Sealed the 3rd November 1868, and dated the 6th May 1868.
PROVISIONAL SPECIFICATION left by the said William Harvie, at the
Office of the Commissioners of Patents, with his Petition, on the
6th May 1868.
I, WILLIAM HARVIE, of Glasgow, in the County of Lanark, North
Britain, do hereby declare the nature of the said Invention of "IMPROVE
MENTS IN THE CONSTRUCTION OF LAMPS AND LANTERNS, AND IN LENSES EMPLOYED
THEREWITH," to be as follows, that is to say:-
This Invention relates, firstly, to certain improvements in the con-
struction of lamps and lanterns, and is particularly applicable to those
used for ships' lights, harbour lights, as well as railway signal, station,
and train lamps, whilst it is also applicable to other purposes. In
carrying it out the lautern in which the lamp is placed is constructed
[Price 8d.1

page_text: in two divisions or chambers with two bottoms enclosing an air space
between them, and connected therewith is a tube or passage passing
down from the top of the lantern, through which the air necessary for
the combustion of the oil in the wick is supplied, the lamp being
double cased and having an air space around it, which communicates
directly with the air space enclosed by the two bottoms herein-before
referred to. The top part of the air space surrounding the lamp is
enclosed by a cap in the ordinary way, through which the flame escapes,
and the entire lamp is enclosed in the lantern by a sliding door, so as
to form a separate chamber and to cut off access in that way with the
atmosphere of the outside chamber. The upper part of the lantern is
also formed double, with a conical cap inside and a hole in its centre,
through which any smoke or unburnt gases given off by the combustion
of the oil escapes. The chimney of the lantern is formed so that, in
the case of a storm, when any air may blow down the top opening it
cannot reach the flame, but is deflected by means of the cone and
escapes through side openings.
The second part of this Invention relates to the formation of dioptric
or other lenses with semicircular ends; it also consists in placing
prisms in the interior of the lens at an angle to the ribs or bands
constituting the dioptric lens proper, and in place of constructing such
lenses by cutting, grinding, and polishing the glass as hitherto, the
Invention also consists in constructing such lenses in moulds made
to the proper form, in which the glass is moulded under pressure, as in
other cases of glass manufacture at present practised.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Harvie in the Great Seal Patent Office on
the 5th November 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HARVIE, of Glasgow, in the County of Lanark, North Britain, sond
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixth day of May, in the year
of our Lord One thousand eight hundred and sixty-eight, in the
thirty-first year of Her reign, did, for Herself, Her heirs and suc-

page_text: cessors, give and grant unto me, the said William Harvie, Her specia]
license, that I, the said William Harvey, my executors, administrators,
and assigns, or such others as I, the said William Harvie, my
executors, administrators, or 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 CONSTRUCTION OF LAMPS AND LANTERNS, AND IN LENSES EMPLOYED
THEREWITH, upon the condition (amongst others) that I, the said
William Harvie, by an instrument in writing under my hand and
seal, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, 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 William Harvie, do hereby declare
the nature of my 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:-
My said Invention relates, firstly, to certain improvements in the
construction of lamps and lanterns, and is particularly applicable to
those used for ships' lights, harbour lights, as well as railway signals
station and train lamps, whilst it is also applicable to other purposes.
In carrying it out the lantern in which the lamp is placed is constructed
in two divisions or chambers with two bottoms enclosing an air space
between them, and connected therewith is a tube or passage passing
down from the top of the lantern through which the air necessary for
the combustion of the oil in the wick is supplied, the lamp being double
cased and having an air space around it, which communicates directly
with the air space enclosed by the two bottoms herein-before referred to.
The top part of the air space surrounding the lamp is enclosed by a
cap in the ordinary way through which the flame escapes, and the entire
lamp is enclosed in the lantern by a sliding door so as to form a separate
chamber and to cut off access in that way with the atmosphere of the
outside chamber. The upper part of the lantern is also formed double

page_text: with a conical cap inside and a hole in its centre through which any
smoke or unburnt gases given off by the combustion of the oil escapes.
The chimney of the lantern is formed so that in case of a storm when
.any air may blow down the top opening it cannot reach the flame,
but is deflected by means of the cone and escapes through side
openings.
The second part of this Invention relates to the formation of dioptric
or other lenses with semi-circular ends.
It also consists in placing prisms in the interior of the lens at an
angle to the ribs or bands constituting the dioptric lens proper. And in
place of constructing such lenses by cutting, grinding, and polishing the
glass as hitherto.
The Invention also consists in constructing such lenses in moulds
made to the proper form in which the glass is moulded under pressure
as in other cases of glass manufacture at present practised.
And in order that ny said Invention may be properly understood,
I now proceed more particularly to set forth the system, mode, or
manner in or under which the same is or may be used or practically
carried into effect, reference being had for the sake of more complete
elucidation to the letters and figures upon the explanatory Sheet of
Drawings which I have hereunto appended, that is to say:-
Figure 1 is a front elovation; Figure 2 a sectional plan on the
line A, A; and Figure 3 a section on the line B, B. On these Figures
similar parts are indicated by corresponding letters of reference.
bottom, the space a
which air is supplied
The lantern L is provided with a double
between them forming an air chamber, from
for combustion to the lamp b. A circular opening is cut in the
inner bottom c; and round the upper side of it a rim is formed over
which an outer casing e on the lamp 6 is placed, and the space a
between the bottoms is enclosed by a perforated plate f, through which
the air is supplied to the annular space g in communication with the
burner h, small tubes i, are also fitted in the inner bottom c, through
which air passes into the inuer chamber ; of the lantern. The air
passes into the lantern by a tube k, Figures 1 and 2, fitted with a
perforated cap 1, and communicates with the outer chamber m by a
tube from whence it passes into the air chamber a by two tubes n, n,
placed one at each side of the lantern, as seen on Figure 2, or air may

page_text: be admitted by tubes passing down the inside of the lantern or through
the bottom. Communication is obtained with the inner chamber j for
the purpose of lighting and trimming the lamp by a sliding door º,
which is fitted in the partition p, and in which a small orifice or sight
hole filled with glass is formed, or it may be formed in the partition p
so that the light may be inspected without opening communication with
the external atmosphere. The smoke or unconsumed gases pass up the
chimney q and the annular space q¹, and escape to the atmosphere by
perforations formed in the conical cap r, which is hinged to the outer
casing at s, and is fastened by a screw t, as shown at Figure 3. The
top of the lantern is enclosed by a cylinder u, to which the handle v is
fixed, as shown on Figure 1, and to prevent gusts of wind passing
down the chimney during a storm the outer casing of the lantern is
carried up inside of the cylinder u and turned over so as to form a bell-
mouthed flanch w, by which means the air is deflected and passes out
by an annular opening at the bottom of the cylinder u; such accidents
are still further guarded against by forming a flanch x round the
conical cap r, as shown on Figure 3. The lantern is furnished with a
dioptric lens C with semicircular ends, and formed in one piece, as
shown, the exterior face of the lens is formed with prismoidal ribs of
the usual form, and the illuminating power of the light is still further
increased by forming prismoidal ribs y on the interior surface of the
lens, as shown on Figures 2 and 3.
Figure 4 is a section of a lamp in which common oils in contra-
distinction to paraffine oil may be burnt, and which may be used in
lanterns constructed according to this Invention. a is the vessel in
which the oil is contained, and the air necessary for combustion is
conveyed to the burner c through the tubes d. An "argand" burner
may also be used as the illuminating apparatus in these lamps.
Having now described the nature of my said Invention, and the
manner in or under which the same is or may be used or practically
carried into effect, I would observe in conclusion that what I consider
novel and original, and therefor claim as the Invention secured to me
by the herein-before in part recited Letters Patent is,―
First. The general arrangement and construction of lamps and
lanterns as shown in the accompanying Drawings and herein-before
described, or any mere modification thereof.

page_text: Second. The arrangement of the lantern into chambers and passages,
as more particularly shown in Figure 3 of the accompanying Sheet of
Drawings, whereby the employment of the ordinary glass chimney is
avoided, and atinospheric currents are prevented from passing down
into the lantern as herein-before described, or any mere modification
thereof.
Third. The construction and arrangement of prismoidal dioptric
lenses, having semicircular ends and vertical prisms formed on the
interior, moulded under pressure in one or more pieces, whereby
cutting is avoided, as herein-before described, or any mere modification
thereof.
In witness whereof, I, the said William Harvie, have hereunto
set my hand and seal, this Fourth day of November, One
thousand eight hundred and sixty-eight.