IMPROVEMENTS IN THE DISTILLATION OF OIL FROM COAL TAR, AND IN APPARATUS FOR PRESERVING TIMBER THEREWITH
Year: 1859

page_text: PROVISIONAL SPECIFICATION left by the said Edward Dorsett and
w
John Bennington Blythe at the Office of the Commissioners-of-Patents,
with their Petition, on the 22nd January 1859.
We, EDWARD DORSETT, of 76, Old Broad Street, in the City of London,
Tär Distiller, and JOHN BENNINGTON BLYTHE, of. Minerva .Place, New Cross,
in the County of Kent, Merchant, do hereby declare the nature of the said
Invention for IMPROVEMENTS IN THE DISTILLATION OF OIL FROM COAL TAR, AND
IN APPARATUS FOR PRESERVING TIMBER THEREWITH," to be as follows:-..
We employ heated retorts, ovens, or stills, set, in, brickwork or fixed in
other suitable manner, connected with the still or, other vessel used for
distilling tar, and attach. thereto pipes and taps in such a manner that the
residue from any distillation may be discharged in its liquid state into the.
ovens, retorts, or stills, either after the termination of the process, or at

page_text: intervals during its continuance, whereby coke may be formed in the ovens
or retorts in layers, and at the discretion of the workman. The tar distiller
being thus enabled to discharge the liquid pitchy matter from the still into
other stills, retorts, or ovens in which the distillation can be continued
without loss of heat, smoke, or expense of removing the pitch after cooling
into the ovens or retorts from whence it can be withdrawn as coke. For
preserving railway sleepers and other timber with tar, oil, sulphate of copper,
or other preservative, we employ an open tank mounted on a suitable
wheel carriage, the said tank being divided into compartments by partitions
furnished with the necessary heating apparatus, and having outlets, or con-
necting pipes, which form junctions. with a vacuum cylinder or closed
compartment of the tank which can be closed at pleasure; the ends of the
said pipes are supplied with perforated plates and washers according to the
size of the timber to be preserved, and at the other end of each compartment
we have screws or other suitable appliances for the purpose of pressing the
sleepers or timber against the perforated plates. Having placed the sleepers
or timber so attached in one compartment of the open tank, we cover it with
creosote or other preservative fluid to any necessary depth, and apply heat
thereto, and having obtained a partial vacuum in the cylinder or chamber
by pumps or other well-known means, we open the connection with the
sleepers through the pipes, and the heated liquid in the tank is drawn through
the sleepers into the vacuum cylinder or chamber; then we place other timber
in another compartiment of the open tank, and the preserving fluid being
let in from the cylinder, the operation is repeated.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edward Dorsett and John Bennington Blythe in the Great
Seal Patent Office on the 22nd July 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, wé, EDWARD
DORSETT, of 76, Old Broad Street, in the City of London, Tar Distiller, and
JOHN BENNINGTON BLYTHE, of Minerva Place, New Cross, in the County of
Kent, Merchant, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her, Letters
Patent, bearing date the Twenty-second day. of January, in the year of
our Lord One thousand eight hundred and fifty-nine, in the twenty-second
year of Her reign, did, for Herself, Her heirs and successors, give and grant
unto us, the said Edward Dorsett and John Bennington Blythe, Her-special

page_text: license that we, the said Edward Dorsett and John Bennington Blythe,
our executors, administrators, and assigns, or such others as we, the said
Edward Dorsett and John Bennington Blythe, our 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 DISTILLATION OF OIL FROM
COAL TAR. AND IN APPARATUS FOR PRESERVING TIMBER THEREWITH," upon the
condition (amongst others) that we, the said Edward Dorsett and John
Bennington Blythe, our executors or administrators, by an instrument in
writing under our, or their, or one of their hands and seals, should parti-
cularly describe and ascertain the nature of the said Invention, and iu
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 we, the said Edward Dorsett and John Bennington
Blythe, do hereby declare the nature of our said Invention, and in what
manner the same is to be performed, to be particularly described and
ascertained in and by the following statement, that is to say :-
We employ retorts, ovens, or stills, heated as nearly as possible to the
temperature of the pitch conveyed to them, which retorts; ovens, or stills are
set in brickwork or fixed in other suitable manner connected with the still or
other vessel used for the distillation of tar, to which we attach pipes and
taps in such a manner that the residue from any distillation may be discharged
in its liquid state into the said ovens, retorts, or stills, either after the termi-
nation of the process or at intervals during the continuation thereof, whereby
coke may be formed in the ovens or retorts' in layers at the discretion of the
workman. The tar distiller being thus enabled to discharge the liquid pitchy
matter from the still or boiler into other stills, retorts, or ovens, heated as
before described, instead of discharging it on the ground in the open air, as
beretofore adopted; the distillation can thus be continued without loss of heat,
smoke,or expense of removing the pitch after cooling on the ground, asalready
stated. By this arrangement the process of distillation of the bituminous.
residue from the treatment of gas tar in the stills or boilers commonly
employed can be carried on by the discharge of portions of the contents of the
stills or boilers to which the retorts are attached at intervals, either during or
immediately after the distillation into the retorts or ovens, and by a séries of
discharges, allowing each portion discharged into the retort or oven to throw

page_text: off its volatile products before allowing other matter to run from the still or
boiler, and a cake of any desired thickness according to the capacity of the
retort or oven employed may be formed therein, thus greatly encreasing the
quantity of oil produced by each oven or retort...
i
Secondly, for the purpose of preserving railway sleepers or other timber
with sulphate of copper or other preservative, we employ a peculiar kind
of vessel or apparatus; constructed and arranged so that the preserving
liquid will not act injuriously upon it.
The manner in which our said improvements are to be performed will be
clearly understood by reference to the accompanying Sheet of Drawings, and
the letters of reference thereon; in which Fig. 1 is a view of our apparatus.
for the distillation of gas tar; Fig. 2, a view of our improved apparatus
for preserving railway. sleepers and other timber with sulphate of copper
or other preservative; and Fig. 3, an outside view of the cover. In Fig. 1, a
represents a boiler; b, b, b, retorts made of iron, clay, or other suitable nictal
or material; and c, a cylindrical retort, the said retorts being laid on brick-
work; and lined with fire-bricks, fire-clay, or other suitable material; d, a feed
pipe by which the hot pitch runs from the still or boiler; e, e, a moveable"
end and crane, by which the retorts are hermetically closed; ff, f, the.
furnaces; 9.9.g,theash-pits; hhh,h,the distillation pipes passing the creosote;
i, the creosote receiver; and, the still head.
.IN
In Fig. 2, representing our improved vessel for preserving timber, a repre-
sents, the, vessel made of staves of wood or other suitable material, of any
desired length and strength, coiled with strong hoops; b, one end of the said
vessel, being fixed, and the other end moveable, or both may be made
muveable if desired, the end or ends being screwed, bolted, or keyed to the
body of the vessel, and also connected together by copper tie bolts c
when great strength is required; d represents the air pipe from the engine;
ethe pressure pipe f, the safety valve; g, the exhausting pipe; h, the blow-
off pipe; i, the door of the cylinder, which is shewn removed from the vessel,
and supported by a crank ; is an iron rim or collar flanged to receive the
door. The tank for holding the solution of sulphate of copper or other
preserving liquid is shewn at m, and the engine house at n. The hoops may.
be made of wood, metal, or strips of wood and metal, and the vessel may
either be plain or lined with lead, gutta percha, or other suitable substance,
upon which the preserving liquid will not be liable to act.
Javing thus fully described the nature of our said, Invention, and the
manner in which the same is to be performed, we desire it to be distinctly.
understood that we do not claim any particular part of the machinery or

page_text: apparatus herein described separately; but we claim as our Invention, and
which to the best of our knowledge and belief has not been hitherto used
within the realm,-
Firstly, the distillation of gas tar by a continuous process from the ordinary
distilling vessel or vessels into other retorts, ovens, or stills, instead of dis-
charging it on the ground, and then re-heating it as hitherto adopted, by
which we obtain a more immediate and plentiful supply of oil by carbonization,
and effect a saving of capital, time, and labor, and dispense with the dangerous,
practice of discharging the pitch in the open air.
And, secondly, the use and application of machinery or apparatus for pre-
serving railways sleepers, or other timber with sulphate of copper or other
preservatives, as such improvements are herein described and illustrated in
the accompanying Sheet of Drawings.
In witness whereof, I, the said Edward Dorsett, for and on behalf of
myself and the said John Bennington Blythe, have hereunto set my
hand and seal, this Twentieth day of July, One thousand eight hundred
and fifty-nine.
EDWARD DORSETT. (L.S.)
Signed, sealed, and delivered by the
within-named Edward Dorsett, in
presence of
EDWARD T. HUGHES, Patent Agent,
123, Chancery Lane, London.