AN IMPROVED PREPARATION OF BLACK LEAD FOR 'POLISHING AND PRESERVING THE SURFACE OF IRON
Year: 1877

page_text: LETTERS PATENT to George Duerr, of Heywood, in the County of Lancaster,
for the Invention of "AN IMPROVED PREPARATION OF BLACK LEAD FOR
'POLISHING AND PRESERVING THE SURFACE OF IRON."
led the 27th April 1877, and dated the 23rd February 1877.
PROVISIONAL SPECIFICATION left by the said George Duerr at the Office
of the Commissioners of Patents on the 23rd February 1877.
GEORGE DUERR, of Heywood, in the County of Lancaster. "AN IMPROVED
PREPARATION OF BLACK LEAD FOR POLISHING AND PRESERVING THE SURFACE
OF IRON."
The object of this Invention is to form a liquid preparation of black lead or
plumbago with other ingredients suitable for polishing stoves, and for other similar.
purposes.
The ingredients and the proportions which I prefer to use are as follows:-About
twenty to thirty per cent. of turpentine, benzoline, or other similar quick drying
and saponifiable substance (turpentine being preferred); about thirty per cent. of
the finest black lead or plumbago, prepared as hereafter mentioned; one-half per
cent. each of cocoa-nut oil and palm oil, saponified, as hereafter described; thirty
per cent. of dilute solution of ammonia (containing about one part of ammonia gas
in ten parts of the solution); one per cent. each of oak bark and sumac, or other
similar substance, containing tannic or gallic acid in the form of a decoction, as
hereafter named; one-half per cent. each of ferrous and ferric sulphates, and
sufficient water to make up the one hundred parts.
To prepare the plumbago I take plumbago or black lead of the finest quality, and
I grind it to as impalpable a powder as possible by the best known method.
To prepare the oak bark and sumac (or other substance containing tannin) I
steam them with a small quantity of water so as to make a strong decoction, and
extract all the tannin principle. I then mix this decoction with the solution of
ferrous and ferric sulphates.
To prepare the cocoa-nut oil and palm oil I saponify them together by means of

page_text: caustic soda, in such a way as to leave no excess of alkali but to obtain a neutral
curd soap.
Having prepared the ingredients in the above described manner I first put the
turpentine (or other similar substance) into a cask or vessel provided with an
agitator, and then add the solution of saponified cocoa-nut oil and palm oil hot. I
next add the ammonia solution by slow degrees, stirring it all the time to effect a
perfect combination. The prepared plumbago is now added, the agitation being
kept up until the whole is well mixed. Lastly, I add the mixture of the decoction
of oak bark and sumac with the solution of ferrous and ferric sulphates.
By this method of preparation, the black lead or plumbago will be held to a con-
siderable extent in a state of mechanical suspension in the liquid, and it may in this
state be used for polishing stoves, and for polishing and preserving other surfaces of
iron.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George Duerr in the Great Seal Patent Office on the 20th August
1877.
GEORGE DUERR, of Heywood, in the County of Lancaster. "AN IMPROVED
PREPARATION OF BLACK LEAD FOR POLISHING AND PRESERVING THE SURFACE
OF IRON."
The object of this Invention is to form a liquid preparation of black lead or
plumbago with other ingredients suitable for polishing stoves, and for other similar
purposes.
The ingredients and the proportions which I prefer to use are as follows:-About
twenty to thirty per cent. of turpentine, benzoline, or other similar quick drying and
saponifiable substance (turpentine being preferred); about thirty per cent. of the
finest black lead or plumbago, prepared as hereafter mentioned; one-half per cent.
each of cocoa-nut oil and palm oil, saponified, as herein-after described; thirty per
cent. of dilute solution of ammonia (containing about one part of ammonia gas in
one hundred parts of the solution); one per cent. each of oak bark and sumach, or
other similar substance, containing tannic or gallic acid in the form of a decoction,
as hereafter named; one-half per cent. each of ferrous and ferric sulphates, and
sufficient water to make up the one hundred parts.
To prepare the plumbago I take plumbago or black lead of the finest quality, and
I grind it to as impalpable a powder as possible by the best known method.
To prepare the oak bark and sumac (or other substances containing tannin) I
steam them with a small quantity of water so as to make a strong decoction, and
extract all the tanning principle. I then mix this decoction with the solution of
ferrous and ferric sulphates.
To prepare the cocoa-nut oil and palm oil I saponify them together by means of
caustic soda in such a way as to leave no excess of alkali but to obtain a neutral
curd soap, or any other neutral soap may be employed.
Having prepared these ingredients in the above described manner I first put the
turpentine (or other similar substance) into a cask or vessel provided with an
agitator, and then add the solution of saponified cocoa-nut oil and palm oil boiling
hot. I next add the ammonia solution by slow degrees, stirring it all the time to
effect a perfect combination. The prepared plumbago is now added, the agitation
being kept up until the whole is well mixed. Lastly, I add the mixture of the
decoction of oak bark and sumac with the solution of ferrous and ferric sulphates.
By this method of preparation the black lead or plumbago will be held to a con-
siderable extent in a state of mechanical suspension in the liquid, and it may in this
state be used for polishing stoves, and for polishing and preserving other surfaces
of iron.

page_text: Having now described the nature and object of my said Invention, I wish it to
be understood that I claim, the preparation of a liquid preparation of black lead or
plumbago, substantially in the manner and for the purposes above more particularly
described.
In witness whereof, I, the said George Duerr, have hereunto set my hand and
seal, this Fifteenth day of August, in the year of our Lord One thousand
eight hundred and seventy-seven.
GEORGE DUERR. (L.S.)