IMPROVE- MENTS IN THE PRODUCTION OF LIGHT BY BURNING OLEIC ACID IN LAMPS, AND IN THE CONSTRUCTION OF LAMPS, AND MANUFACTURE OR PREPARATION OF OLEIC ACID POR THAT PURPOSE
Year: 1848

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, we, GEORGE
FERGUSSON WILSON, of Belmont, Vauxhall, in the County of Surrey, Gentle-
inan, and CHARLES HUMFREY, of Manor Street, Old Kent Road, in the said
County of Surrey, Merchant, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-eighth day of
December, One thousand eight hundred and forty-eight, in the twelfth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto us,
the said George Fergusson Wilson and Charles Humfrey, our exors, adñiors,
and assigns, Her especial license, full power, sole privilege and authority, that
we, the said George Fergusson Wilson and Charles Humfrey, our exors,
adñiors, and assigns, or such others as we, the said George Fergusson Wilson
and Charles Humfrey, our exors, admors, 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 expressed, should and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, in the
Islands of Guernsey, Jersey, Alderney, Sark, and Man, and also in all Her
said Majesty's Colonies and Plantations abroad, our Invention of "IMPROVE-
MENTS IN THE PRODUCTION OF LIGHT BY BURNING OLEIC ACID IN LAMPS, AND IN
THE CONSTRUCTION OF LAMPS, AND MANUFACTURE OR PREPARATION OF OLEIC ACID
POR THAT PURPOSE;" in which said Letters Patent is contained a proviso that
we, the said George Fergusson Wilson and Charles Humfrey, should cause a
particular description of the nature of our said Invention, and in what manner
the same is to be performed, by an instrument in writing under our hands

page_text: and seals, or under the hand and seal of one of us, to be inrolled in Her
said 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, we, the
said George Fergusson Wilson and Charles Humfrey, do hereby declare that
the nature of our said Invention, and the manner in which the same is to be
performed, are fully described and ascertained in and by the following state-
ment thereof, reference being had to the Drawing hereunto annexed, and
to the figures and letters marked thereon, that is to say :-
Our Invention consists in the construction of lamps to burn oleic acid for
the purpose of illumination. Oleic acid is obtained in several ways, among
others in the manufacture of stearic acid by the saponification of fatty and oily
matters and subsequent decomposition by some mineral acid; but oleic acid so
obtained, and which is commercially designated "tallow oil,".contains so much
impurity as to render it in most cases unfit, or nearly unfit, for burning in
lamps, but the oleic acid obtained by the improved method of making stearic
acid by acidification of fatty matters, and subsequent distillation, yields an acid
of great purity; and we prefer oleic acid so obtained; preferring in all cases
to distil or redistil the oleic acid before employing it in lamps. The nature
and properties of oleic acid are well known, but there is one peculiarity in
which it differs from cómmon oils that renders it essential-that-the lamps.for
burning it should be constructed upon the principles herein-after described.
The ordinary oils may be subjected to a very considerable heat without being
in the least injured; on the contrary, most of them burn in lamps better for
being pretty strongly heated before they flow into the wick where they are
consumed; while oleic acid, exposed to a greatly inferior heat, under like
circumstances is decomposed, and a black pitchy substance formed which
prevents its burning: This will readily be seen by trimming an ordinary oil
lamp with oleic acid; for a short time the burning will proceed extremely well,
the oleic acid from its nature burning more freely and brightly than any of.the
ordinary oils, but so soon as the burner or 'burner tube becomes hot enough
(and this soon happens) to decompose the oleic acid; there is an immediate
formation in the wick of this black pitchy substance, which progressively
prevents its further action, and the lamp goes out. And we have found it
essential in burning such description of oil to cause the burner.or. tube con-
taining the cotton wick to be kept cool, so that the oil may not become heated
to a decomposing degree before it arrives above-the tube or burner; for which

page_text: reason we construct lamps in such manner that the oleic acid is never exposed
to the heat of decomposition before its actual combustion in the wick. It will
be observed, after lighting. lamps containing oleic acid, that for some short time
after. it is lighted the flame remains as shewn in-the adjoining Figure, where
a, a, Fig 2, is the top of the burner tube, and b, b, the base of the flame, so
that there is a small space of unblackened cotton interposed between the
flame and the metal of the burner tube. So long as this state of things
continues (the radiant. heat of the flame being but trifling) the burner
tube is scarcely heated at all; this, however, soon ceases, and the flame
descends until it touches the top of the burner tube, and the oleic acid by
reason of its great inflammability (unless some contrivance be added to
preserve this non-conducting interval of wick) quickly inflames, and the flame
almost immediately runs down to the inner tube, which by actual contact
becomes strongly heated, and the oleic acid is decomposed. This descent
of the base of the flame we find can easily be prevented by directing on
the wick, just immediately above the top of the burner tube and below
the base of the flame, a current of air by any convenient means. Wo
have employed a plate shewn in Figure 1, which effectually prevents
the descent of the flame, and consequently prevents the heating of the
burner tube, and in such lamps oleic acid can be burnt well. We do not
confine ourselves to the precise form of such lamps, as the same may be varied
so long as the construction be such as to prevent oleic acid becoming heated
to a decomposing degree till it rises above the burner tube. We would
remark, that the oil being injurious (by reason of its acid character) to brass,
which is the metal usually employed for making lamps, it is desirable to plate
the parts liable to be acted on by the acid oil.
We will now describe that part which consists of preparing oleic acid for
the purpose of burning in lamps. Heretofore it has been usual to employ acid
diluted with water as a means of purifying oleic acid, and in agitating such
matters to apply artificial heat. We have found that heat is prejudicial, and
that oleic acid, simply well agitated with diluted acid (we use sulphuric acid)
without the addition of artificial heat, produces the requisite degree of purifi-
cation, and in a superior manner to that when heat is used.
In witness whereof, we, the said George Fergusson Wilson and Charles
Humfrey, have hereunto set our hands and seals, this Twenty-sixth
day of June, in the year of our Lord One thousand eight hundred and
fortu ning
GEO. F. (L.s.) WILSON.
CHARLES (L.s.) HUMFREY.

page_text: AND BE IT REMEMBERED, that on the Twenty-sixth day of June, in
the year of our Lord 1849, the aforesaid George Furgusson Wilson and
Charles Humfrey came before our said Lady the Queen in Her Chancery, and
acknowledged the Specification aforesaid, and all and every thing therein
contained and specified, in form above written. And also the Specification
aforesaid was stamped according to the tenor of the Statute made for that
purpose.
Enrolled the Twenty-eighth day of June, in the year of our Lord One
thousand eight hundred and forty-nine.