IMPROVED APPARATUS FOR THE DIFFUSION OF LIGHT, CALLED ILLUMINATORS
Year: 1854

page_text: LETTERS PATENT to Emile Chappuis, of St. Mary Axe, City of London,
for the Invention of "IMPROVED APPARATUS FOR THE DIFFUSION OF LIGHT,
CALLED ILLUMINATORS."
Sealed the 22nd August 1854, and dated the 27th February 1854.
PROVISIONAL SPECIFICATION left by the said Emile Chappuis at the
Office of the Commissioners of Patents, with his Petition, on the 27th
February 1854.
I, EMILE CHAPPUIS, of St. Mary Axe, City of London, do hereby declare
the nature of the said Invention for "IMPROVED APPARATUS FOR THE DIFFUSION
OP LIGHT, CALLED ILLUMINATORS," to be as follows:-
This Invention consists of the use of figured surface glass as an illuminator,
or reflector and refractor of natural or artificial light. The figured surfaces
may be of rectilineal, angular, conic, cylindric, prismoidal, or other curved
forms, and the back thereof may be coated or covered with quicksilver or other
opaque substance, or not, and may be made of Bohemian or coloured glass, in
forms or shapes to suit the purpose for which the illuminator is required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Emile Chappuis in the Great Seal Patent Office on the
26th August 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EMILE
CHAPPUIS, of St. Mary Axe, City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of February, in the year of our
Lord One thousand eight hundred and fifty-four, in the seventeenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Emile Chappuis, Her special licence that I, the said Emile Chappuis,
my executors, administrators, and assigns, or such others as I, the said Emile
Chappuis, my 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 "AN IMPROVED APPARATUS FOR THE
DIFFUSION OF LIGHT, CALLED AN ILLUMINATOR," upon the condition" (amongst
others) that I, the said Emile Chappuis, 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 Emile Chappius, 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:-
!
My Invention has for its object the 'better diffusion or. reflection of solar
light, and is adapted for general use in shops, counting-houses, factories, and
private dwellings where there may be a partial deprivation of incident light-
metallic reflectors, or as they are called day light or diurnal reflectors, have
been much used of late for throwing light into dark offices, shops, &c., but not
with uniform success. In many instances these reflectors wholly fail to give
the required light, owing to the fact, that the luminous molécules, on approach-
ing the quasi reflecting medium, are subjected to the action of forces arising
from this medium, which decompose and neutralize them.
.
In some instances tin-foil has been used in place of, if not sold for, polished
metal, and, as is obvious, the reflective qualities of such a material are of very
weak power, to say nothing of the want of permanency or non-capacity of

page_text: resisting atmospheric influences of such a flimsy substance. Again, owing to
ignorance on the part of unskilful operatives, who undertake to make cheap
reflectors, the reflectors are fixed at such angles as to become refractors rather
than reflectors, practically useless for the intended purpose. Admittedly, the
best metallic reflector for diffusing solar light is that denominated Chappuis
myriastratic, for which Her most Gracious Majesty Queen Victoria, granted
to me Her Letters Patent bearing date the Twentieth day of April, in the year
Eighteen hundred and fifty-three.
In this reflector a large number of angles are presented to the action of
the incident light, causing greater diffraction, and consequently more emerging
light.
My myriastratic reflectors have been tried in every position and for every
purpose, and when judiciously applied, with certain modifications, adapted to
each particular locale, they give off the greatest amount of light that the
highest reflecting medium affords. I have found, however, in some instances,
that metallic reflectors are not so ornamental, and perhaps not so useful, as
those made wholly or in great part of glass. For lighting up highly-decorated
shops and gentlemen's mansions, these glass reflectors are well adapted. But
in order that my Invention may be well understood, I will proceed to describe
the manner in which I construct this improved apparatus for the diffusion of
day light. The reflecting medium is glass, of a prismatic form, joined together
in plates, and retained by a frame of gutta percha, glass, wood, or other
material, and cemented, if needful, with Bohemian cement, or other viscous
matter. The plates or sheets of glass used for this purpose are to be pressed
in moulds, constructed so as to give to one of the surfaces the forms of prisms,
or of figures of a prismatic character, the other surface being plain. These
plates are to be cemented together, or attached by means of rivets of silver
wire, or by any other suitable means, until the required size of the reflector is
obtained; then they are to be fixed in the grooves of the case, which may be
either of gutta percha, or other material, cement, or other adhesive matter
being used, if required, to make the joints tight. This reflector is then to be
fixed at the proper angle outside a house, shop, or in any other position in
which the solar light may reach it, and be reflected and diffused. Prisms have
a peculiar refracting power, and when placed in juxtaposition, the alternate
refraction and reflection produces that dispersion of the molecules which dis-
seminates light, the law of optics in this regard being one well defined, that the
direction of the incident and refracted ray is always in a plane perpendicular
to the surface common to the media.
Having now described the nature of my said Invention, and how the same

page_text: is to be performed, I desire to be understood as reserving a right to vary the
details of my Invention; and, in particular, I do not restrict myself to the use of
prismoidal figures, as curved forms may be used, and the back of the reflector
may be coated with mercury, and part of the said reflector may be made of
Bohemian or colored glass. But what I claim is, the construction of an
illuminator or day light reflector in the manner herein described, wherein glass
prisms are used, connected together in the manner described.
In witness whereof, I, the said Emile Chappuis, have hereunto set my
hand and seal, this Twenty-sixth day of August, in the year of our
Lord One thousand eight hundred and fifty-four.
EMILE CHAPPUIS. (L.S.)