IMPROVEMENTS IN THE PREPARATION OF DISINFECTING AND ANTISEPTIC SUBSTANCES." PREPARATION OF DISINFECTING AND ANTISEPTIC SUBSTANCES
Year: 1859

page_text: LETTERS PATENT to Alexander McDougall, of Manchester, in the County
of Lancaster, Chemist, for the Invention of "IMPROVEMENTS IN THE
PREPARATION OF DISINFECTING AND ANTISEPTIC SUBSTANCES."
PREPARATION OF DISINFECTING AND ANTISEPTIC SUBSTANCES."
Sealed the 26th June 1860, and dated the 28th December 1859.
PROVISIONAL SPECIFICATION left by the said Alexander McDougall,
at the Office of the Commissioners of Patents, with his Petition, on the
28th December 1859.
I, ALEXANDER MODOUGALL, of Manchester, in the County of Lancaster,
Chemist, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN THE PREPARATION OF DISINFECTING AND ANTISEPTIC SUBSTANCES," to be as
follows:-
My improvements consist in dissolving what is commonly called the
"dead oil" or heavy oil of tar, derived either from the distillation of coal or
wood in water mixed with an alkali or an alkaline earth; but as the peculiar
odour of the oil is removed, and its solubility is increased by the action of an
acid, I prefer to act upon it with an acid previously to dissolving it in the alkali
or the alkaline earth and water. The solution thus obtained, either with or
without the treatment of the oil with an acid, I use for the disinfection of
sewage and other matters liable to putrefactive fermentation.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alexander McDougall, in the Great Seal Patent Office on
the 28th June 1860...
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MCDOUGALL, of Manchester, in the County of Lancaster, Chemist, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of December, in the year of our
Lord One thousand eight hundred and fifty-nine, in the twenty-third year of
Her Majesty's reign, did, for Herself, Fer heirs and successors, give and grant
unto me, the said Alexander McDougall, Her special licence that I, the said
Alexander McDougall, my executors, administrators, and assigns, or such
others as I, the said Alexander McDougall, 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 "IMPROVEMENTS IN THE PREPARATION OF DISINFECTING AND ANTI-.
SEPTIC SUBSTANCES," upon the condition, amongst others,. that I, the said
Alexander McDougall, 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 Alexander M°Dougall, 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 :-
My improvements consist in dissolving what is commonly called the
"dead oil" or heavy oil of tar, derived either from the distillation of coal or
wood in water mixed with an alkali or an akaline earth; but as the peculiar
odour of the oil is removed and its solubility is increased by the action of an
acid, I prefer to act upon it with an acid previous to dissolving in the alkali
or the alkaline earth and water. The solution thus obtained either with or
without the treatment of the oil with an acid, I use for the disinfection of
sewage and other matters liable to putrefactive fermentation. The acid I
prefer to use is nitric acid, and I find about three parts of acid to one hundred
parts of oil to answer the purpose. The manner in which I carry out my

page_text: Invention is as follows:-I take for example one hundred pounds of the oil
and add to it about three per cent. of commercial nitric acid; I then agitate
this mixture in as much lime water (with a little excess of lime) as may be
necessary to dissolve it. I then allow it to stand until the excess of lime has
subsided, when the clear liquor is ready for use in the treatment of sewage or other
putrescible matters. The action of the liquor produced as above is strongly
antiseptic, and prevents organic substances from becoming putrescent. I
therefore prefer to apply it while the matters to be acted upon are as recent as
convenient. If the sewage or other matters have already undergone decompo-
sition I prefer to add a small per-centage of a metallic salt to the oil after
treatment with the acid for the purpose of decomposing any sulphuretted or
phosphuretted hydrogen, or any sulphides or phosphides already formed and liable
to give off any of these gases, the quantity to be used in each case being deter-
mined by the condition of the substance; but I have found two per cent. to
answer the purpose.
Having thus described and ascertained the nature of my said Invention and
the manner of carrying the same into effect, I desire it to be understood that
I claim,
First, the use of heavy oil of tar, derived from the distillation of coal, wood,
or analogous substances dissolved in water by the use of alkali or alkaline
earths for the disinfection of sewage or other matters liable to putrefactive
fermentation.
Secondly, the previous treatment of the heavy oil of tar with an acid to
remove its peculiar odour and to increase its solubility.
In witness whereof, I, the said Alexander McDougall, have hereunto set
my hand and seal; this Twenty-third day of June, in the year of our
Lord One thousand eight hundred and sixty.
Witness,
J. W. Moffatt,
66, Chancery Lane.
A. MCDOUGALL. (LS.)