AN IMPROVED METHOD OF PREVENTING PREMATURE, DECAY IN, TIMBER, METALLIC, SUBSTANCES, AND CANVAS, BY THE APPLI- CATION WHEREOF TO SUCH SEVERAL BODIES RESPECTIVELY THE SAME ARE RESPECTIVELY RENDERED IMPERVIOUS TO THE DRY ROT, WORMS, INSECTS, OR RUST, TO WHICH THE SAME ARE RESPECTIVELY LIABLE, AND THE SAME ARE THEREBY RENDERED MORE DURABLE, AND LESS LIABLE TO DECAY
Year: 1822

page_text: granted to JOHN OXFORD,.
Dritam,
in the City of London, Gentleman, for "AN IMPROVED METHOD OF PREVENTING
PREMATURE, DECAY IN, TIMBER, METALLIC, SUBSTANCES, AND CANVAS, BY THE APPLI-
CATION WHEREOF TO SUCH SEVERAL BODIES RESPECTIVELY THE SAME ARE RESPECTIVELY
RENDERED IMPERVIOUS TO THE DRY ROT, WORMS, INSECTS, OR RUST, TO WHICH THE
SAME ARE RESPECTIVELY LIABLE, AND THE SAME ARE THEREBY RENDERED MORE
DURABLE, AND LESS LIABLE TO DECAY," .dated November First, One, thousand
eight hundred and twenty-two,,in. the third year of the reign of our Sovereign
Lord George, the Fourth, by the grace of God of the United Kingdom of
Great Britain and Ireland.King, Defender of the Faith.
TO ALL TO WHOM. THESE PRESENTS SHALL COME, I, JOHN
OXFORD, of Little Britain, in the City of London, Gentleman, send greeting.
WHEREAS His present Majesty. George the Fourth, in and by His
Letters Patent under..the Great. Seal of Great Britain, bearing, date at
Westminster, the First. day of November, in the third year of the reign
of His.said present Majesty, hath.given and granted unto me, the said John
Oxford, mý..executors,. administrators, and assigns, His especial, licence, full
power, sole privilege. and authority, that I, my executors, administrators,, and
assigns, and every of them, by myself and themselves, or by. my or their
deputy or deputies, servants or. agents, or such others as I, my executors,
administrators or assigns, shall at any time agree with, and no others, from
time to time and at all. times hereafter during the term of years..therein

page_text: expressed, should and lawfully might make, use, exercise, and vend my
Invention and Improved Method of Preventing Premature Decay in Timber,
Metallic Substances, and Canvas, by the Application whereof to such Several
Bodies respectively the same are respectively rendered Impervious to the Dry
Rot, Worms, Insects, or Rust, to which the same are respectively Liable, and
the same are thereby rendered more Durable and less Liable to Decay; and
that I, my exccutors, administrators, and assigns, should have and enjoy the
full benefit and the sole use and exercise of the said - Invention, for and
during and unto the full end and term of fourteen years from the date of the
said Letters Patent, according to the Statute in such case made and provided;
and whereas in the said Letters Patent there is a proviso that if I, the said
John Oxford, shall not particularly describe and ascertain the nature of my
said Invention, and in what manner the same is to be performed, by an instru-
ment in writing under my hand and seal, and cause the same to be inrolled
in His Majesty's High Court of Chancery within two calendar months next
and immediately after the date of the said Letters Patent, that then the said
Letters Patent, and all liberties and advantages whatsoever thereby granted,
shall utterly cease, determine, and become void.
NOW KNOW YE, that I, the said John Oxford, do hereby particularly
describe and ascertain the nature of my said Invention, and in what manner
the same is to be performed, as follows:-
Innumerable have been the methods suggested, and particularly to the
public authorities, for the prevention of that dreadful scourge, the dry rot,
but the desired effect seems to have been but partial. From the known anti-
septic properties of coal tar, it has of late years been resorted to in various
forms and for various purposes, but it does not appear to me that it has
hitherto been applied in the most efficacious manner; and I found my
objection to these applications from the plain fact that the essential oil of the
tar, and which is the sole preservative contained therein, is by the present
methods principally evaporated and not absorbed by the substances to which
it has been applied. I have therefore, after long and assiduous study, dis-
covered the means whereby this said volatile oil becomes fixed, and, without
losing the least particle of its penetrative quality, it assumes the same
unctuous tenacity of linseed or nut oils. I treat it as follows:-Particular care
must be taken that the oil be divested of all impurities whatsoever, which
when done it is in fact neither more nor less than pure naphtha. I put it into
proper receivers, containing from two hundred and fifty to five hundred gallons
.each, to which alembics are adapted; I then saturate the oil with chlorine gas
by passing a stream of the said gas from the alembics through the oil. This

page_text: process must be very carefully watched, and must be stopped as soon as the
saturation is complete, and the oil has imbibed or absorbed a sufficient
quantity of the chlorine, which is ascertained as follows: the appearance of the
oil will be changed from the opaque muddy black colour to a claret red, and
3 instead of the light watery substance of the volatile oils it will assume a
gelable appearance; and if the weather be very warm during the operation, it
may be known by plunging a phial filled with oil for a minute or two into a
vessel of cold water; the disagreeable empyreumatic smell will be greatly
diminished, altho' it cannot be completely overcome, without at the same time
destroying the oleaginous principle; it is in fact changed from a volatile to a
fixed oil without the least injury to its penetrative qualities. The oil thus
prepared is ready for use, that is to say, for mixing and grinding with the
materials or component parts of the coating which is proposed to be laid over
or spread upon the substances intended to be preserved. These materials or
component parts consist of the following articles, viz, of every one hundred
parts thereof I take fifty parts of white lead, or of the red oxide (according
to the colour required), twenty-five other parts of carbonate of lime well
washed, and the remaining twenty-five parts of carbon of purified coal tar.
These ingredients are to be mixed with the oil, prepared as above stated, in
large mash tubs, and must be suffered to remain twenty-four hours before the
process of grinding is commenced, in order to give time for the slight effer-
yescence which takes place, occasioned by the escape of carbonic acid gas.
The process of grinding and mixing the materials above mentioned with the
oil is the same as that which is used by colourmen in preparing their oil paints,
namely, that it is ground as stiff as possible, that a due proportion of the oil
for liquefying the compound for use should accompany it; and in case of two
or more coatings being intended to be laid on when the compound is to be
applied to timber, the first covering should be laid on very thin in order that it
should imbibe as much of the oil as possible; the thick coating or coatings
intended to follow will prevent any escape of the oil absorbed by the timber.
The whole of the ingredients, particularly the carbon of the purified tar, has
such an affinity for the oil that it will require nearly weight for weight in the
application. The penetrative quality of this compound is truly astonishing.
If applied to timber that has been regularly painted for fifty years (which has
been ascertained by actual trial) the oil will penetrate to the surface of the
wood, whilst the solid parts unite with the old paint which the oil had pre-
viously rendered soft; and in this stage the whole may be easily scraped of, or
if suffered to remain, will become an impenetrable covering, and in all cases,
when it is dry, the smell arising therefrom will cease. The utility of this

page_text: compound ás a preventive is founded on the antiséptic qualities of the fluid;
and the indestructibility of the solids. The carbon of refined coal, as far as
prepared by me, is the same coal tar still, but changed in appearance, in the
same manner that flowers of sulphur bear to roll brimstone. Timber thus
prepared has been subjected to the most violent test for the space of two
years without the slightest appearance of change, except that it had assumed a
greater degree of hardness; but it is not to be expected that this or any other
preparation can have the desired effect if applied to green timber, neither does
it follow that it is necessary to extirpate every particle of the vegetable juice;
on the contrary, if a portion thereof be left, and is prevented from exuding by
an external application, it will inspissate and thereby strengthen the timber.
The fatal effects of dry rot has been for many years past the theme of general
complaint, nor does anything seem to be less understood. Those who appear to
have given the subject the most of their attention have been obliged to wind
up their observations by merely remarking that it is one of the many methods
adopted by nature' for hastening the decomposition of all matter when deprived
of animal or vegetable life, in order that it may, by being sooner reduced to its
primeval form, become the sooner capable of supporting future animal ör
vegetable existence. The term, however, by which it is known is undoubtedly a
gross misnomer, for humidity, whether on shore or afloat, is its great supporter.
In buildings it has been attributed to a plant of the creeping kind, the produce
of the soil; but how happens it that this disease; when it occurs on board of
ships that are either constantly afloat or in dry docks, assumes invariably
the sanie appearance as buildings when under the same influence? To discover
the cause of any effect is undoubtedly the surest way to find a remedy, but in
this case something hitherto has always occurred to baffle the attempt. The
judicious measures adopted by the authorities now presiding over His Majesty's
Naval Department will, doubtless, tend to lessen the evil, as far as it extends
to the Navy; the admirable method of stacking their timber, and of building
and repairing their ships under cover; are stupendous undertakings, and worthy
of the first maritime nation in the world; but even with those precautions dry
rot is of such an insidious nature, that I believe even in that quarter other
means are deemed necessary. In all cases where timbers are scarfed or dove-
tailed, or where they are wedged together without any intervening substance,
there is sure to be the commencement of decay, which a thick coating of the
compound will effectually prevent, as it stands in all climes, being neither
affected by heat or cold. When applied to iron or any other metal the
adhesive power of the compound effectually excludes the operation of oxygen
on the surface, and of course preserves it from decay.

page_text: With respect to its application to canvas, or any other linen substance, it is
recommended to lay on the first coat very thick, whereby the interstices may
be completely closed and rendered impervious to rain, or any other moisture.
In witness whereof, I, the said John Oxford, have hereunto set my
hand and seal, the day and year first above written.
Signed, sealed, and delivered in the
presence of
ROBT BARBER,
JUHN
(L.S.) OXFORD.
Fetter Lanc,
Attorney-at-Law.
ROB POULMIN,
His Clerk.
AND BE IT REMEMBERED, that on the Thirty-first day of December,
in the third year of the reign of His Majesty King George the Fourth, the
said John Oxford came before our said Lord the King in His Chancery, and
acknowledged the Instrument aforesaid, and all and every thing therein con-
tained and specified, in form above written. And also the Instrument aforesaid
was stamped according to the tenor of the Statute made in the fifty-fifth year of
the reign of His late Majesty King George the Third.
Inrolled the Thirty-first day of December One thousand eight hundred