Improvements in the Preparation and Production of Bodies for Use in what is known as Incandescent Gas Lighting.
Year: 1895

page_text: Date of Application, 14th Dec., 1895
Complete Specification Left, 14th Sept., 1896-Accepted, 28th Nov., 1896
PROVISIONAL SPECIFICATION.
Improvements in the Preparation and Production of Bodies for Use
in what is known as Incandescent Gas Lighting.
I PROSPER BARRIÈRE, of 7 Rue de Rome, Paris, in the Republic of France,
Engineer do hereby declare the nature of my invention to be as follows:-
:-
Incandescent gas lighting, which consists in suspending fire-proof luminous
substances within the flame of a Bunsen burner, has been carried out hitherto in
several different ways.
The illuminating properties possessed by various metallic oxides such as those of
zirconium, lanthanium, yttrium, thorium, and magnesium, have suggested the idea
of making these oxides serviceable as luminous bodies.
The distinctive features of the various metallic oxides hitherto employed have
been precisely determined from the points of view of both physical science and
chemistry.
These oxides are derived from 'corresponding ores, such as thorite, cerite,
gadolinite, zircon, and the like.
The treatment of these ores is a question which has not as yet been 'fully cleared
up, and I shall not attempt to deal with it, inasmuch as my own efforts have been
directed to the study of other minerals.
But the numerous experiments which I have made have enabled me to discover,
and to satisfy myself of, the presence of a novel illuminating body (I will refer to
it under the letter A) in a special ore of a sandy nature, obtainable at different
places and known as monazited sand.
This body has properties different from those possessed by the substances used
hitherto.
The ore, which possesses a sandy appearance, is really rich river loam, found in
small ruby-like pebbles.
The following is an example of an analysis made on a sample of this substance:
(SiO') Silica
69.7 %
(PO) Phosphoric acid
(FeO3) Iron
(APO) Alumina
Cerium, lanthanium, didymium about
Lime, magnesia and other miscellaneous matter about
Moisture
"A" body
-
6
1.92%
15
2.13
이
2.05 %
2- %
1:80%
This new body "A" enters into the composition of the ores named in the
proportion of from 1.5 to 6% according to the sample dealt with.
TREATMENT.
The composition indicated above necessitates special methods of treatment
having for their object to eliminate any harmful substance which the body treated

page_text: The ore, on having been porphyrized, is slowly melted in suitable furnaces, with
an addition of carbonate of sodium in the proportion of one part of ore for every
two parts of carbonate. This operation which takes about three hours to complete
is intended to convert the oxides into insoluble carbonates.
After cooling, the powdered mass is lixiviated. Then by means of decantation,
the elimination of the silicates and phosphates of sodium is proceeded with.
When the carbonates are exhausted by the water, they are subjected to the
action of sulphuric acid, the surplus of which is eliminated by slow calcination.
The sulphates are dissolved in cold water and precipitated by means of ammonia.
The precipitate, on being washed, is dissolved in hydrochloric acid, care being
taken to properly neutralize it.
The greater part of the iron and alumina is then removed by precipitating it by
means of oxalic acid.
The insoluble oxalates are converted into sulphates, when partial calcination in
a muffle-furnace is proceeded with.
This calcination is interrupted at a certain period of the operation, which,
however, can only be determined by taking into account the appearance of the
material under treatment; the proper time for this being when the greater part of
the acid has been eliminated. The sulphates obtained are then pulverized and put
in cold water in small quantities, so that the saturation stage is as nearly as possible
reached.
The solution obtained is then precipitated by means of ammonia, whereby
magnesia and the salts of lime are eliminated.
Then, by filtering, a gelatinous precipitate of oxides is obtained, which is
dissolved in sulphuric acid.
The sulphuric solution obtained, having had sulphate of sodium in solution,
saturated while cold, added to it, is used as a precipitating medium, there being
crystals in suspension in the mass, and the saturated solution being allowed to
digest for from five to six hours. Thus the group: cerium, lanthanium, didymium
is precipitated.
The double sulphates thus obtained are filtered and the liquid is re-precipitated
by means of ammonia, and then thoroughly washed.
In order to remove thorium, the solution is made in sulphuric acid, and the
precipitate obtained by means of sulphate of potassium.
Thus all the bodies mentioned above, as being present with the "A".body, may
be eliminated.
Now the principal operation of the process has to be commenced. It consists in
precipitating the solution by means of hyposulphite of sodium in the condition of a
concentrated solution. This operation is started with a slight action of heat.
When the boiling point is reached, the "A" body is precipitated first. The body
obtained contains, as impurities, small quantities of yttrite earths, principally
ytterbite.
It only remains, after this, to effect a most thorough washing of the insoluble
byposulphite thus obtained, using cold water for the purpose. After the washing,
a solution is made in hydrochloric acid.
A reaction with sulphocyanide of ammonia will at that moment show whether
there are any, traces of iron left, and these, if present, may then be eliminated by
the ordinary methods.
In the same way, traces of other metallic substances may be eliminated by means
of a current of sulphuretted hydrogen sent into the solution of hydrochloric acid.
After precipitation by means of ammonia, the body is energetically washed with
distilled cold water.
By such means a body is obtained which, in itself, is luminous, and which is
made use of in the manner which I will now describe.
Generally speaking the oxides employed for illuminating purposes, as well as the
body to which I have referred just now, produce light which is illuminating and
radiating only to a certain degree.

page_text: Radiation, which constitutes the illuminating power proper, and more particularly
the brilliancy desirable in a luminous body, is obtained owing to the molecular
condition which I have found to be realizable with exceptional ease in a body
which, after many trials, I have discovered to be oxide of zinc. Any other body
fulfilling the same conditions may, however, be employed without departing from
the principle of the invention.
•
Oxide of zinc which upon being heated at an ordinary temperature assumes a
greenish-yellow hue, when subjected to the heat of a Bunsen burner, becomes
phosphorescent as it were. It is sufficient to add a small percentage of it to the
illuminating solution.
I employ a nitric solution of the oxide in question.
After a fabric, which should be as fibrous as possible, has been impregnated
with the said solution when the wick thus formed has been incinerated, the
decomposition of the nitrates will take place under the most favourable conditions
conceivable.
Part of the oxide of zinc,-the surplus thereof, is volatilized, while the
remainder will be in that molecular condition referred to just now.
It is not impossible to use other oxides which, if employed under certain
conditions, and mixed or combined in a certain definite manner, and either
combined or not with the "A" body,-may form novel bodies.
The fabric which I employ is made of special thread or filament, such as the
fibres of flax, China grass, or the like, and it should have about 90 meshes per
square centimetre. It is washed in a one tenth solution of hydrochloric acid and
then with water having a slight amount of ammonia incorporated in it.
The fabric after drying is cut into strips of say 20 centimetres and strengthened
at their upper part with a strip of muslin or tulle.
Impregnation may be advantageously substituted by aspersion, by means of a
special injector, which process offers the advantage of not necessitating protracted
baudling of the fabric, whereby certain impurities might find their way into it.
The bath employed is a nitric aqueous solution, containing as much as 10% of
the luminous body. Each wick should absorb at least 6 cubic centimetres.
After the wick has been placed on a special form or mould it is secured to a
hanger of nickel by means of an asbestos thread.
A Bunsen flame is rapidly and circularly passed round the upper portion of the
said wick, while another burner is worked from below.
Incineration will then take place, and the earths will form gradually.
By such means, a species of skeleton is obtained which is placed over a burner
for about half an hour in order to secure complete calcination.
The wick is then in readiness for being supplied in a marketable form, and may
be fitted to any burner.
Dated this 14th day of December 1895.
6 Improvements in the Preparation and Production of Bodies for Use
in what is known as Incandescent Gas Lighting.
I, PROSPER BARRIÈRE of 7 Rue de Rome, Paris, in the Republic of France
Engineer do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by the
0 following statement :-
Incandescent gas lighting which consists in suspending fire-proof luminous

page_text: substances within the flame of a Bunsen burner has been carried out hitherto in
several different ways.
The illuminating properties possessed by various metallic oxides such as those
of zirconium, lanthanium, yttrium, thorium, and magnesium, have suggested the
idea of making these oxides serviceable as luminous bodies.
The distinctive features of the various metallic oxides hitherto employed have
been precisely determined from the points of view of both physical science and
chemistry.
These oxides are derived from corresponding ores, such as thorite, cerite, gado-
linite, zircons, and the like.
The treatment of these ores is a question which has not as yet been fully
cleared up, and I shall not attempt to deal with it, inasmuch as my own efforts have
been directed to the study of other minerals.
But the numerous experiments which I have made have enabled me to discover,
and to satisfy myself of, the presence of a novel illuminating body (I will refer to
it under the letter A) in a special ore of a sandy nature, obtainable at different
places and known as monazited sand.
This body has properties different from those possessed by the substances used
hitherto.
The ore, which possesses a sandy appearance, is really rich river loam, found in
small ruby-like pebbles.
The following is an example of an analysis made on a sample of this
substance :-
(SiO³) Silica
(PO) Phosphoric acid
(Fe2O³) Iron
69.7%
6
1.92°
15
(A10) Alumina -
Cerium lanthanium, didymium about
Moisture -
Lime, magnesia, and other miscellaneous matter
about
"A" body
T
.
2
1
2.13%
2.05%
2
%
1.80%
1
The composition indicated above necessitates special methods of treatment
having for their object to eliminate any harmful substances which the body treated
may contain.
The purity of this body is the main condition upon which a satisfactory yield
depends.
The ore, on having been porphyrized, is slowly melted in suitable furnaces, with
an addition of carbonate of sodium in the proportion of one part of ore for every
two parts of carbonate. This operation which takes about three hours to complete
is intended to convert the oxides into insoluble carbonates.
After cooling, the powdered mass is lixiviated. Then, by means of decantation,
the elimination of the silicates and phosphates of sodium is proceeded with.
When the carbonates. are exhausted by the water, they are subjected to the
action of sulphuric acid, the surplus of which is eliminated by slow calcination.
The sulphates are dissolved in cold water and precipitated by means of ammonia.
The precipitate, on being washed, is dissolved in hydrochloric acid, care being
taken to properly neutralize it.
The greater part of the iron and alumina is then removed by precipitating it by
means of oxalic acid.

page_text: The insoluble oxalates are converted into sulphates, when partial calcination in a
muffle-furnace is proceeded with.
This calcination is interrupted at a certain period of the operation, which,.
however, can only be determined by taking into account the appearance of the
material under treatment; the proper time for this being when the greater part of
the acid has been eliminated. The sulphates obtained are then pulverised and put
in cold water in small quantities, so that the saturation stage is as nearly as possible
reached.
The solution obtained is then precipitated by means of ammonia, whereby
magnesia and the salts of lime are eliminated.
Then, by filtering, a gelatinous precipitate of oxides is obtained, which is
dissolved in sulphuric acid.
The sulphuric solution obtained, having had sulphate of sodium in solution,
saturated while cold, added to it, is used as a precipitating medium there being
crystals in suspension in the mass, and the saturated solution being allowed to
digest for from five to six hours. Thus the group: cerium, lanthanium, didymium
is precipitated.
The double sulphates thus obtained are filtered and the liquid is re-precipitated.
by means of ammonia, and then thoroughly washed.
In order to remove thorium, the solution is made in sulphuric acid, and the
precipitate obtained by means of sulphate of potassium.
Thus all the bodies mentioned above, as being present with the "A" body, may
be eliminated.
Now the principal operation of the process has to be commenced. It consists in
precipitating the solution by means of hyposulphite of sodium in the condition of a
concentrated solution. This operation is started with a slight action of heat.
When the boiling point is reached, the "A" body is precipitated first. The body
obtained contains, as impurities, small quantities of yttrite earths, principally
ytterbine.
It only remains, after this, to effect a most thorough washing of the insoluble.
bypo-sulphite thus obtained, using cold water for the purpose. After the washing,.
a solution is made in hydrochloric acid.
A reaction with sulphocyanide of ammonia will at that moment show whether
there are any traces of iron left, and these, if present, may then be eliminated by
the ordinary methods.
In the same way, traces of other metallic substances may be eliminated by means:
of a current of sulphuretted hydrogen sent into the solution of hydrochloric acid.
After precipitation by means of ammonia, the body is energetically washed with
distilled cold water.
By such means a body is obtained which, in itself, is luminous, and which is made.
use of in the manner which I will now describe.
Generally speaking the oxides employed for illuminating purposes, as well as the
body to which I have referred just now, produce light which is illuminating and
radiating only to a certain degree.
Radiation, which constitutes the illuminating power proper, and more particularly
the brilliancy desirable in a luminous body, is obtained owing to the molecular
condition which I have found to be realizable with exceptional ease in a body
which, after many trials, I have discovered to he oxide of zinc. Any other body
fulfilling the same conditions may, however, be employed without departing from
the principle of the invention.
Oxide of zinc which upon being heated at an ordinary temperature assumes a
greenish yellow hue, when subjected to the heat of a Bunsen burner, become
phosphorescent as it were. It is sufficient to add a small percentage of it to the
illuminating solution.
I employ a nitric solution of the oxide in question.
After a fabric, which should be as fibrous as possible, has been impregnated
with the said solution when the wick thus formed has been incinerated, the

page_text: decomposition of the nitrates will take place under the most favorable conditions
conceivable.
Part of the oxide of zinc,-the surplus thereof,-is volatilized, while the
remainder will be in that molecular condition referred to just now.
It is not impossible to use other oxides which, if employed under certain
conditions, and mixed or combined in a certain definite manner, and either
combined or not with the "A" body,-may form novel bodies.
The fabric which I employ is made of special thread or filament, such as the
fibres of flax, China grass, or the like, and it should have about 90 meshes per
square centimetre. It is washed in a one tenth solution of hydrochloric acid and
then with water having a slight amount of ammonia incorporated in it.
The fabric after drying is cut into strips of say 20 centimetres and strengthened
at their upper part with a strip of muslin or tulle.
Impregnation may be advantageously substituted by aspersion, by means of a
special injector, which process offers the advantage of not necessitating protracted
handling of the fabric, whereby certain impurities might find their way into it.
The bath employed is a nitric aqueous solution, containing as much as ten
per cent. of the luminous body. Each wick should absorb at least 6 cubic
centimetres.
After the wick has been placed on a special form or mould it is secured to a
banger of nickel by means of an asbestos thread.
A Bunsen flame is rapidly and circularly passed round the upper portion of the
said wick, while another burner is worked from below.
Incineration will then take place, and the earths will form gradually.
By such means, a species of skeleton is obtained which is placed over a burner
for about half an hour in order to secure complete calcination.
The wick is then in readiness for being supplied in a marketable form, and may
be fitted to any burner.
The novel illuminating body which I have referred to as "A" I have named
"lucium."
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what I
claim is :-
1. For incandescent gas lighting, a new body, derived from monazited sands,
substantially as hereinbefore described.
2. For incandescent gas lighting the body "A," referred to in the preceding
claim, in combination with a small percentage of oxide of zinc or other body
capable of imparting the necessary intensity and power of radiation as hereinbefore
specified.
3. The purification of the "A" body, referred to in the first claim, by treating
monazited sands with oxalic acid, sulphate of sodium, sulphate of potassium, and
hyposulphite of sodium, substantially as described.
4. For incandescent gas lighting the combination of the aforesaid body A (either
alone or in combination with other bodies as indicated in the second claim) with
fibres, or filaments; substantially as and for the purpose herein before specified.
Dated this 14th day of Sentember 1896.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents..