AN IMPROVED SYSTEM OF LIGHTING BY MEANS OF COLORED GLASSES
Year: 1878

page_text: LETTERS PATENT to William Edward Gedge, of No. 11; Wellington Street,
Strand, London, in the County of Middlesex, Patent Agent, for the Invention
of "AN IMPROVED SYSTEM OF LIGHTING BY MEANS OF COLORED GLASSES."
A communication from abroad by Louis Michel, of "Thonon (Haute Savoie),
France
PROVISIONAL SPECIFICATION left by the said William Edward Gedge at
the Office of the Commissioners of Patents on the 28th October 1878.
WILLIAM EDWARD GEDGE, of No. 11, Wellington Street, Strand, London, in the
County of Middlesex, Patent Agent. "AN IMPROVED SYSTEM OF LIGHTING BY
MEANS OF COLORED GLASSES.' A communication from abroad by Louis Michel,
of Thonon (Haute Savoie), France.
This Invention relates to a system of coloring the globes, chimneys, and shades of
lamps or other lighting apparatuses whereby the best kind of lights may be obtained
for the particular sight of the person using the lamp, and also for the circumstances
under which it is used or for the employments carried on by its light.
The new oils, the cheapness of which has rendered their use almost universal,
such, for example, as the hydrocarbon oils, petroleum, and others, have in addition
to their cheapness the relative advantage of a bright and uniform light; I say
relative; because this light invariably brilliant, and which when the radiation takes
place upward or obliquely is no longer moderated by the eyebrows, the eyelids, and
the eyelashes, cannot fail in the end to cause pertubations of sight. But these per-
tubations are owing to another cause, more decisive, more rapid, more calamitous in
its results; and which has hitherto remained unnoted, namely, to the glasses of

page_text: whatever shape used in lighting apparatuses with the object of concentrating the
luminous rays and of preserving the flame from any vacillation. The upper part of
these glasses forms a luminous focus, usually-brought nearer to the sight than the
lighted_object_upon which attention is directed. There escapes therefrom oblique
diverging rays, which as they cannot be sufficiently refracted make impressions
_ upon the retina.at other points than those where the rays of the visual cone should
unite, which may already be prejudicial to the clearness of the image.
-In-the-end the result is an irritation of-this-membrane, of which the circular fibres
of the iris feel the re-action. The contractions of these fibres to produce the
shrinking of the pupil become more frequent and forced, a painful kind of dazzling or
dimness often follows, and, as most persons must have experienced; after-an
instinctive backward movement the hand is instinctively brought before the eyes
as if to drive away the cloud which appears interposed between the eyes and the
light. But the first effect of these frequent contractions is that the movements of
the eyelids are more numerous, following each other much quicker. Now for clear-
ness of sight the existence of an exact proportion between the duration and the
frequency of these movements is absolutely necessary; they must be short enough
to prevent the sight of the objects being too long suspended, and sufficiently
multiplied to prevent too long an excitation of the surface of the cornea.
From the foregoing it will be seen how important it is for the preservation of the
eyes and for clearness of sight to do away with or to neutralise the effects of the
above-mentioned luminous focus.
It is believed that this object is attained by the diversified coloration of the globes
and glasses used in lighting apparatuses according to the circumstances of their
requirement.
On the accompanying Sheet of Drawing forming part of this Provisional Speci-
fication :-
No. 1 indicates chimneys and shade suitable for needlework or the study. The
glass is colored a deep blue to within about 3. centimeters of the flame. This shade
is sympathetic to the sight and throws a slightly azure tint upon the objects to be
seen. By means of the bulb chimney this model will be advantageously employed
for lamps burning petroleum, neoline, and analogous oils:
No. 2. This globe and chimney should be used when it is desired to spread the
light over a greater area. Same shade or a deep grenat or ruby placed at the
upper part of the globe, which it divides horizontally. The chimney is the same
color as the globe down to the level of the luminous part.
The lighting part will be higher or lower according to the expansion to be given
to the light; it may even rise to half the height of the globe, according to the size
of the apartment and the number of persons requiring the light.
No. 3. Employed as shown in this Figure this globe will increase the lighting
-power-while-relieving-the.sight; it will be very useful for schoolrooms and reading-
rooms. Further, its application will be found advantageous, 1°, for shop fronts,
colored blue for white woven fabrics, or of various colours for articles. of different
shades of color; 2°, for roads, bridges, and street corners; and an important point
independent of its elegant effect is that by varying the shades of color systematically
it may be made to serve as a guide to travellers.
No. 4. Reversed as in this Figure and covered with a light shade the globe colored
horizontally will give for the benefit of the sick a soft light from above similar to
that of daybreak, which is so cheering to the invalid. In dormitorys it will permit
the scholars to sleep without obstacle while there will be light enough for a proper
supervision.
No. 5. This Figure shows the same arrangement but on a larger scale to give
analogus advantages in hospitals and large dormitorys.
No. 6. This Figure shows a globe colored vertically (of a crimson shade) for use
in drawing-rooms or salons; to groups in conversation it will give a softened light,
while the lighting part will spread over the rest of the apartment a bright light,
J

page_text: which will permit other persons present to play at games, to read, or work. This
arrangement may also be very advantageously used in sick rooms.
No. 7. This Figure shows auother application of the vertically colored globe and
chimney very suitable for theatres and lecture halls, where the dark part of the
globe may be turned towards the speaker or lecturer.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Edward Gedge in the Great Seal Patent Office on the
22nd April 1879.
WILLIAM EDWARD GEDGE, of No. 11, Wellington Street, Strand, London, in the
County of Middlesex, Patent Agent. "AN IMPROVED SYSTEM OF LIGHTING BY
MEANS OF COLORED GLASSES." A communication from abroad by Louis Michel,
of Thonon (Haute Savoie), France.
This Invention relates to a system of coloring the globes, chimneys, and shades
of lamps or other lighting apparatuses whereby the best kind of light may be
obtained for the particular sight of the person using the lamp, and also for the
circumstances under which it is used or for the employments carried on by its
light.
The new oils, the cheapness of which has rendered their use almost universal,
such, for example, as the hydrocarbon oils, petroleum, and others, have in addition
to their cheapness the relative advantage of a bright and uniform light; I say
relative, because this light, invariably brilliant, and which when the radiation takes
place upward or obliquely is no longer moderated by the eyebrows, the eyelids, and
the eyelashes, cannot fail in the end to cause pertubations of sight. But these per-
tubations are owing to another cause more decisive, more rapid, more calamitous in
its results, and which has hitherto remained unnoted, namely, to the glasses, of
whatever shape, used in lighting apparatuses with the object of concentrating the
luminous rays and of preserving the flame from any vacillation. The upper part
of these glasses forms a luminous focus, usually brought nearer to the sight than
the lighted object upon which attention is directed. There escapes therefrom
oblique diverging rays, which as they cannot be sufficiently refracted make
impressions upon the retina at other points than those where the rays of the
visual cone should unite, which may already be prejudicial to the clearness of the
image.
In the end the result is an irritation of this membrane, of which the circular
fibres of the iris feel the re-action. The contractions of these fibres to produce the
shrinking of the pupil become more frequent and forced, a painful kind of dazzling
or dimness often follows, and as most persons must have experienced after an
instinctive backward movement the hand is instinctively brought before the eyes
as if to drive away the cloud which appears interposed between the eyes and the
light. But the first effect of these frequent contractions is that the movements of
the eyelids are more numerous, following each other much quicker. Now for clear-

page_text: ness of sight the existence of an exact proportion between the duration and the
frequency of these movements is absolutely necessary; they must be short enough
to prevent the sight of the objects -being-too long suspended and sufficiently
- multiplied to prevent to long an excitation of the surface of the cornea.
From the foregoing it will be seen how important it is for the préservation of
_the_eyes.and.for clearness of sight to do. away with or to neutralise the effects of
the above-mentioned luminous focus.
-It-is-believed that this object is attained by the diversified coloration of the
globes and glasses used in lighting apparatuses according to the circumstances of
their requirement.
On the accompanying Sheet of Drawing forming part of this Specification,
No. 1 indicates chimneys and shade suitable for needlework or the study. The
glass is colored a deep blue (to within about 3 centimeters of the flame). This
shade is sympathetic to the sight and throws a slightly azure tint upon the objects
to be seen. By means of the bulb chimney this model will be advantageously
employed for lamps burning petroleum, neoline, and analogous oils.
No. 2. This globe and chimney should be used when it is desired to spread the
light over a greater area. Same shade or a deep grenat or ruby placed at the
upper part of the globe, which it divides horizontally. The chimney is of the same
color as the globe down to the level of the luminous part.
The lighting part will be higher or lower according to the expansion to be given
to the light; it inay even rise to half the height of the globe, according to the size
of the apartment and the number of persons requiring the light.
No. 3. Employed as shown in this Figure this globe will increase the lighting
power while relieving the sight; it will be very useful for schoolrooms and reading-
rooms; further, its application will be found advantageous, 1°, for shop fronts,
colored blue for white woven fabrics, or of various colours for articles of different
shades of color; 2°, for roads, bridges, and street corners, and an important point
independently of its elegant effect is that by varying the shades of color systemati-
cally it may be made to serve as a guide to travellers.
No. 4. Reversed as in this Figure and covered with a light shade the globe
colored horizontally will give for the benefit of the sick a soft light from above,
similar to that of daybreak, which is so cheering to the invalid; in dormitorys it
will permit the scholars to sleep without obstacle, while there will be light enough
for a proper supervision.
No. 5. This Figure shows the same arrangement but on a larger scale to give
analogous advantages in hospitals and large dormitorys.
No. 6. This Figure shows a globe colored vertically (of a crimson shade) for use
in drawing-rooms or salons. To groups in conversation it will give a softened
light, while the lighting part will spread over the rest of the apartment a bright
light, which will permit other persons present to play at games, to read, or work,
This arrangement may also be very advantageously used in sick rooms.
No. 7. This Figure shows another application of the vertically colored globe and
chimney very suitable for theatres and lecture halls, where the dark part of the
globe may be turned towards the speaker or lecturer to relieve his sight and permit
him to see the effect he is producing upon his audience. The spectators in a theatre
will feel similar comfort; the indicated shade of color will spread over the
physiognomy a rosy tint, the beautifying effect of which will be generally
appreciated.
This same model may also be very usefully employed in infirmaries and hospitals,
it will give the double effect of giving abundance of light to the superintendants,
and of leaving to the patients a soft and beneficial degree of light; even the doctor
will appreciate the advantage of being enabled when required to easily ascertain
the condition of the patient by simply turning towards him the part giving fuller
light.
By means of these various models the inventor believes that he has obviated the
principal pertubations of the sight above mentioned, and particularly in the

page_text: preceding paragraph. As to the shades of color the choice will necessarily be left
to the persons using these apparatuses.
Having now described and ascertained the nature of the said Invention, com-
municated to me as aforesaid, and in what manner the same is or may be performed,
I claim as secured to me by the herein-before in part recited Letters Patent,-
The system of lighting by means of colored glasses substantially as herein-before
described and illustrated on the accompanying Sheet of Drawing, this system being
based upon the coloration of the globes, chimneys, and shades.
In witness whereof, I, the said William Edward Gedge, have hereunto set
my hand and seal, this Twenty-second day of April, in the year of our
Lord One thousand eight hundred and seventy-nine.
W. E. GEDGE. (L.S.)