IMPROVE- MENTS IN THE MANUFACTURE OF BREAD, AND IN APPARATUS TO BE EMPLOYED THEREIN
Year: 1858

page_text: LETTERS PATENT to Johann Von Nepomuk Siegmund Petrziwalsky, of
Pall Mall, in the County of Middlesex, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF BREAD, AND IN APPARATUS TO BE EMPLOYED
THEREIN."
Sealed the 30th September 1858, and dated the 20th July 1858.
COMPLETE SPECIFICATION filed by the said Johann Von Nepomuk
Siegmund Petrziwalsky at the Office of the Commissioners of Patents,
with his Petition and Declaration, on the 20th July 1858, pursuant to
the 9th Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHANN
VON NEPOMUK SIEGMUND PETRZIWALSKY, of Pall Mall, in the County of
Middlesex, send greeting.
WHEREAS I, the said Johann Von Nepomuk Siegmund Petrziwalsky,
have petitioned Her Majesty to grant unto me, my executors, administrators,
and assigns, Her Royal Letters Patent for an Invention for "IMPROVEMENTS
IN THE MANUFACTURE OF BREAD, AND IN APPARATUS TO BE EMPLOYED THEREIN :"
NOW KNOW YE, that I, the said Johann Von Nepomuk Siegmund
Petrziwalsky, do hereby declare the nature of my said Invention, and in what
manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement and the Drawings therein referred
to (that is to say) :—

page_text: My Invention, which has reference, firstly, to an improved method of
mixing and preparing dough for the purpose of making all descriptions of
fancy bread, with or without ferment, so as to render the same lighter and
more easy of digestion, and at the same time capable of being more readily
moulded into and baked in fanciful forms than hitherto, consists in com-
municating or imparting to the said compound when in an unprepared and
moistened state, a tearing or separating action, so as to deprive it of its dense
or plastic nature, and cause a perfect separation of its particles, by which the
same is rendered porous, and consequently capable of being more readily
acted upon by the heat than by the present method of kneading or working
the dough. To effect which I cause proportionate quantities of flour, meal, or
otherwise, to be placed within suitable troughs or receptacles for being mixed,
to which may be added leaven previously prepared or used in its natural state;
water or other liquid should then be applied in sufficient quantities, until the
ingredients are effectually commingled, and the mass has attained the usual
consistency, when the operation of tearing or separating the particles as afore-
said is commenced and continued until the dough is deprived of its superfluous
moisture, and rendered sufficiently porous by inflation, as above described;
the dough thus treated may then be formed or divided into various figures or
devices, powdered or coated with flour made from Indian corn and placed
within the oven to be baked, having previously been submitted to the process
of proving or rising when necessary.
And, seconly, my Invention, which relates to the apparatus to be used in
the manufacture of bread, consists of a new or improved form and construction
of oven, by which greater uniformity of heat is obtained, and the bread
rendered less subject to be overbaked than at present.
But in order that my said Invention may be more fully understood and
readily carried into effect, I now proceed to describe it by the aid of the
accompanying Drawings, reference being had to the letters and figures thereon
marked (that is to say):
Fig. 1 represents a front elevation of my improved oven; Fig. 2, a longi-
tudinal vertical section taken through-the-dotted line in Fig. 1; Fig. 3, a
horizontal section taken through the dotted line in Fig. 2; Fig. 4, a top or plan
view, partly in section, of the front portion of the same; Fig. 5, a transverse
vertical section taken through the centre of the oven; Fig. 6, a sectional side
view of the regulating draft flue separately shown; and Fig. 7, a detached
inside view of the oven door, showing the arrangement of the plate for pre-
venting the escape of the upper surface heat from the oven.
In each Figure
the same letters of reference denote similar corresponding parts.

page_text: A, A, the outer wall of the oven; B, B, projecting flue shaft; C, C, shaft
communicating with the atmosphere for the discharge of the smoke; D, D,
the oven; E, E, the oven door; F, F, moveable plate for preventing the
escape of heat from the oven on the opening of the door; G, G, crank handle
for raising and lowering the same when required; H, H, tubular flues com-
municating from the interior of the oven to the flue shaft B, as in manner
shown; I, I, caps or valves for opening and closing the communication
between the ends of the said tubular flues and the flue shaft; J, J, handles
for actuating the same; K, K, wall plates through which the same work;
L, L, regulating valve or flue opening for increasing or diminishing the draft, as
required; M, M, lantern or glazed opening formed in the wall of the oven, for
illuminating the same through the medium of a gas burner N, N, or otherwise;
O, O, metallic block secured to the side and bottom of the oven in such
manner as to be readily acted upon by the fire during the process of heating
the same, so as to admit of a jet of water through the medium of a pipe and
stop-cock P and P¹, flashing into steam, by being directed against its surface;
Q, Q, wood or fuel, by which the oven is heated; R, R, various forms of
bread placed in the oven for baking; S, S, body or brickwork of the oven.
In conclusion to the foregoing description I would here briefly note, that in
order to make the necessary preliminary arrangements for baking so as to
obtain an uniform temperature within the oven during the process, I cause
the caps or valves I, I, to be closed on the fire being removed and the oven
cleaned out, by which the circulation of the draft is cut off, and the escape of
heat prevented; the bread is then placed within the oven for eight to ten
minutes, during which period steam, generated in small jets within the oven,
is caused to act upon the bread through the medium of the jet of water and
heated metallic block, the effect of which upon the crust or outer surface of
the bread produces a glazed or vitrified appearance, without the employment
of other agents, as at present. And I would further note, that by the arrange-
ment of the lantern or glazed opening M, M, in the front of the oven in
connection with the moveable plate F, F, I am enabled to watch or ascertain
the progress of the operation of baking, and by the employment of the caps or
valves I, I, and regulating valve L, L, to vary the temperature as required.
Having now fully described the nature of this my said Invention, and the
manner in which the same is to be performed, I would have it clearly under-
stood that I do not intend to limit myself to the precise details herein-before
set forth, as the same might be varied without departing from the general
principle of these my said improvements; but that which I do claim as new
and of my said Invention is, the method herein-before described of tearing or

page_text: separating the particles of dough, in connection with the general- form and
construction of the apparatus, in the manner and for the purposes herein.
before set forth and described.
In witness whereof, I, the said Johann Von Nepomuk Siegmund
Petrziwalsky, have hereunto set my hand and seal, this Twenty-ninth
day of June, in the year of our Lord One thousand eight hundred
and fifty-eight.
J. PETRZIWALSKY. (L.S.)
Witness,
F. R. DARKIN CAMPBELL,
Clerk to Messrs. Weatherdon & Co.,
77; Chancery Lane.