CERTAIN IMPROVEMENTS IN THE PREPARATION OF MATERIALS TO BE EMPLOYED FOR PRODUCING ILLUMINATION
Year: 1845

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
CLARK, of Red Cross Street, Cripplegate, in the City of London, Oil Merchant,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Thirty-first day of October, in the ninth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Henry Clark, Her especial license, full power, sole privilege and authority, that
I, the said Henry Clark, my executors, administrators, and assigns, and such
others as I, the said Henry Clark, my executors, administrators, or assigns,
should at any time agree with, and no others, from time to time and at all
times during the term of years therein mentioned, should and lawfully might
make, use, exercise, and vend, within England, Wales, and the Town of Ber-
wick-upon-Tweed, and in all Her Majesty's Colonies and Plantations abroad,
and in the Islands of Jersey, Guernsey, Alderney, Sark, and Man, my Invention
of "CERTAIN IMPROVEMENTS IN THE PREPARATION OF MATERIALS TO BE EMPLOYED
FOR PRODUCING ILLUMINATION;" in which said Letters Patent is contained
a proviso obliging me, the said Henry Clark, by an instrument in writing
under my hand and seal, particularly to describe and ascertain the nature
of my said Invention, and in what manner the same is to be performed,

page_text: and to cause the same to be enrolled in Her Majesty's High Court of
Chancery within six calendar months next and immediately after the date of
the said in part recited Letters Patent, as in and by the same, reference
being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Henry Clark, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, is particularly described and
ascertained in and by the following description thereof (that is to say) :-
My improvements in the preparation of materials to be employed for pro-
ducing illumination consist in a novel mode or process by which an essential
oil produced from the distillation of resin may be purified and rendered a fit
substitute for oil, capable of being burned in lamps and employed in other
situations. The most economical material which I can use is the essential oil
obtained by the distillation of the rosin of commerce, commonly called rosin
oil, or pine spirit. This material, produced in any of the known ways, I take
(say one gallon), and after placing it in an earthen, wooden, metallic, or other
suitable vessel, I introduce the purifying matter. This purifying matter
consists of caustic potash, soda, or lime, mixed with water in the proportion of,
say, to one pint of water from eight to sixteen ounces of the caustic material,
but I do not confine myself to these limits, as they may be varied according to
the condition of the essential oil or spirit to be acted upon; that is to say,
when the oil or spirit is more foul than usual, or contains a great quantity of
colouring matter, then I employ the larger quantity of the caustic material. Into
the vessel containing the said gallon of essential oil or spirit I introduce from
one to four pints of the caustic solution (either in a cold or warm state), the
quantity of the solution required depending upon its strength, and the condition
of the spirit or essential oil, which is a matter that cannot be readily defined
except in a general way. I would therefore say that the oil of rosin in its usual
commercial state will be properly acted upon by a solution of eight ounces of
the caustic material in a quart of water applied to a gallon of the essential
oil. These materials being introduced into the vessel as above said, must be
agitated continually for the space of from one to two hours, and when the
mixture has been so treated it may be allowed to settle for about twelve
hours, and being then drawn off and filtered through a layer of cotton wool
and animal charcoal fresh calcined, it is in a fit or purified condition for burn-
ing and for commerce. When I require the essential oil to be brought to a
more purified condition, I take the material from the vessel in which it has
been acted upon by the caustic alkali, and submit it to a process of distillation.
And here I would observe, that I prefer to introduce the caustic materials

page_text: with the essential oil into the still in order that they may be distilled together,
which produces the best result; but I sometimes distil the essential oil when
drawn off from the alkaline solution without the caustic material, merely
introducing into the still a quantity of water sufficient to prevent the oil from
charring; or I can effect the same object by introducing into the still a jet of
high-pressure steam. The essential oil, after it has passed through the still,
must then be subjected to filtration through cotton wool and charcoal, as
before said.
Having now described my improved mode of preparing materials to be
employed for producing illumination, I must observe, that I do not intend to
confine myself to the use of oil of resin alone, but apply my process of purifi-
cation to any description of essential oil obtained from resinous substances,
I therefore desire it to be understood that my Invention, and that which I
claim under the above in part recited Letters Patent is,-
Firstly, treating resinous essential oils with caustic alkali in the way
described, for the purpose of purifying such oils; and,
Secondly, a further process of purifying the said oils by means of distillation,
as above said.
In witness whereof, I, the said Henry Clark, have hereunto set my hand
and seal, this Thirtieth day of April, in the year of our Lord One
thousand eight lundred and forty-six.
Inrolled the same Thirtieth day of April, in the year above written.