PRODUCING AN OXY-HYDRO-MAGNESIAN LIGHT APPLICABLE TO PHOTOGRAPHIC PURPOSES, TO LIGHTHOUSES, AND TO OTHER ILLUMINATIONS
Year: 1865

page_text: LETTERS PATENT to Thomas Parker, of 42, Saint Mary Axe, in the City of
London, Clerk to Messrs. Charles Albert Pellas and Company of the same
Place, Merchants, for the Invention of "PRODUCING AN OXY-HYDRO-MAGNESIAN
LIGHT APPLICABLE TO PHOTOGRAPHIC PURPOSES, TO LIGHTHOUSES, AND TO OTHER
ILLUMINATIONS."-A communication from abroad by Prospero Carlevaris,
of Genoa in the Kingdom of Italy. Professor of Chemistry
Sealed the 15th May 1866, and dated the 15th December 1865,
PROVISIONAL SPECIFICATION left by the said Thomas Parker at the
Office of the Commissioners of Patents, with his Petition, on the 15th
December 1865.
I, THOMAS PARKER, of 42, Saint Mary Axe, in the City of London, Clerk
to Messrs. Charles Albert Pellas and Company, of the same Place, Merchants,
do hereby declare the nature of the said Invention for "PRODUCING AN
OXY-HYDRO-MAGNESIAN LIGHT APPLICABLE TO PHOTOGRAPHIC PURPOSES, TO LIGHT-
HOUSES, AND TO OTHER ILLUMINATIONS," to be as follows:-
The process whereby this light can be obtained is founded upon the
following scientifical principles:-
1. The infusibility of oxide of magnesium at the very highest temperature.

page_text: 2. The property that the said oxide has of being volatilized, but in the
smallest quantity in a flame of oxygen and hydrogen mixed together, and
without imparting any color to that flame.
3. The property that the same oxide has of spreading, on being placed
within the flame of the said combination of gases, an intense, bright, and
constant light, and which is admirably suited to photography and general
illumination.
4. The property that many magnesian salts, and particularly chloride of
magnesium and carbonate of magnesia have of leaving, on being decomposed
at such high temperature as is produced by burning together oxygen and
hydrogen gases, some oxide of spongy magnesium.
Starting from these principles to obtain the light spoken of the process is as
follows: A piece of chloride of magnesium, larger or smaller according to
the effects of light required, is placed upon a small prism of gas-retort coal,
and upon it, through a small tube purposely made, the flame of the oxy-
hydrogen gas (the mixture of oxygen and hydrogen) is directed. Or, a prism,
or even a small and well compressed cylinder, of carbonate of magnesia, is
placed within the flame from the same mixed gases. The chloride of magnesium,
or the carbonate of magnesia, is directly decomposed and resolved into oxide
of spongy magnesium, from which the intense, bright, fixed, and constant
light comes forth, causing all the chemical phenomena of diffused sunlight.
The gases of the said combination, which are pure hydrogen, or even
ordinary illumination gas, and pure oxyden, or even atmospherical air, flow
separately from two different gasometers, and are mixed only in a very small
tube at the end of the pipes. They can be prepared in the ordinary way
when wanted in small quantities; if wanted on a large scale, pure hydrogen
is prepared by causing steam to pass over incandescent charcoal. Oxygen is
prepared with manganese and hypochlorite of lime, with manganese and silicic
acid, or with dry sulphate of iron, the products of whose decomposition are
caused to pass upon platinated pumice-stone, turning to profit the sulphurous
acid resulting from the process to the preparation of sulphites.
3
"
The Invention, therefore, consists in producing a light by placing the oxide
of spongy magnesium in a flame produced by a mixture of oxygen and
2

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed,
by the said Thomas Parker in the Great Seal Patent Office on the
21st May 1866.
.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
PARKER, of 42, Saint Mary Axe, in the City of London, Clerk to Messrs.
Charles Albert Pellas & Co., of the same Place, Merchants, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifteenth day of December, in the year of our'
Lord One thousand eight hundred and sixty-five, in the twenty-ninth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Thomas Parker, Her special licence that I, the said Thomas Parker,
my executors, administrators, and assigns, or such others as I, the said
Thomas Parker, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times there.
after 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 " PRO-
DUCING AN OXY-HYDRO-MAGNESIAN LIGHT APPLICABLE TO PHOTOGRAPHIC PURPOSES,
TO LIGHTHOUSES, AND TO OTHER ILLUMINATIONS," upon the condition (amongst
others) that I, the said Thomas Parker, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
and seals, 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 Thomas Parker, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement (that is to say):-
This oxy-bydro-magnesian light consists of a new process for producing an
intense, bright, and constant light applicable to photographic purposes, to
lighthouses, and to other illuminations. The process whereby this light can
be obtained is founded upon the following scientific principles:
-
1. The infusibility of oxide of magnesium at the very highest temperature.
2. The property that the said oxide has of being volatilized, but in the
smallest quantity at a very high temperature, so that it can stand and keep.

page_text: for a long while even in a flame of oxygen and hydrogen mixed together, and
without imparting any colour to that flame.
3. The property that the same oxide has of spreading on being placed
within the flame of the said combination of oxygen and hydrogen gases an
intense, bright, and constant light, and which is admirably suited to nocturnal
photography, to lighthouses, and general illumination.
4. The property that the spongy oxide of magnesium has of being the best
of all magnesium oxides to produce the oxy-hydro-magnesian light. Spongy
oxide of magnesium is prepared by exposing at such high temperature as is
produced by burning together oxygen and hydrogen gases, many magnesian
salts, and particularly chloride of magnesium and carbonate of magnesia
which on being decomposed at such high temperatures turn into spongy oxide
of magnesium.
Starting from these principles to obtain the light spoken of the process is
as follows:-A piece of chloride of magnesium (same chloride of magnesium
that melts into metallic magnesium), larger or smaller according to the
effects of light required, is placed either upon a small prism of gas-retort
coal, or of refractory clay, or else is placed between two small platinum wires,
and upon such a piece through a small tube purposely made the flame of the
oxy-hydrogen gas (the mixture of oxygen and hydrogen) is directed. Larger
or smaller pieces like prisms or cylinders can also be cut out of well com-
pressed carbonate of magnesia and then placed to the same effect within the
flame from the said oxy-hydrogen gas. The chloride of magnesium or the
carbonate of magnesia at such high temperatures as are produced by burning
together oxygen and hydrogen gases are directly decomposed and resolved
into spongy oxide of magnesium, from which the intense, bright, fixed, and
constant light comes forth, causing all the chemical phenomena of diffused
sunlight. It is not required that the hydrogen and oxygen should be chemi-
cally pure, carburetted hydrogen or common lighting gas can be used instead
of pure hydrogen. Atmospherical air, pure or mixed with,,,,, of
its own volume of oxygen can also be used instead of pure oxygen. The two
gases, let them be pure, or ordinary lighting gas, and atmospherical air, con-
taining more or less oxygen, must come from two different gasholders
through two separate pipes, and must be mixed only at the end of these pipes
in a very small tube, forming in that manner a real chalumeau (oxy-hydrogen
soldering pipe, or pipe to burn oxygen and hydrogen together). Oxygen to
be mixed or not with atmospherical air must be prepared according to the most
recent and economical methods that are more suitable to the very country

page_text: where the new process of illumination is to be adopted. The Invention
therefore consists in producing a light by placing the oxide of spongy
magnesium in a flame produced by a mixture of oxygen and hydrogen.
In witness whereof, I, the said Thomas Parker, have hereunto set my
hand and seal, this Twenty-first day of May, in the year of our Lord
One thousand eight hundred and sixty-six.
THOMAS PARKER. (L.B.)