THE IMPROVEMENT OP STOVES FOR THE PURPOSE OF WARMING ROOMS AND BAKING BREAD, CALLED THE HYGEIAN STOVE."
Year: 1858

page_text: LETTERS PATENT to John Emil Ryffel, of Wimbledon, in the County of
Surrey, for the Invention of "THE IMPROVEMENT OP STOVES FOR THE
PURPOSE OF WARMING ROOMS AND BAKING BREAD, CALLED THE HYGEIAN
STOVE.""
Sealed the 9th August 1858, and dated the 13th February 1858.
PROVISIONAL SPECIFICATION left by the said John Emil Ryffel at
the Office of the Commissioners of Patents, with his Petition, on the
13th February 1858.
I, JOHN EMIL RYFFEL, of Wimbledon, in the County of Surrey, do hereby
declare the nature of the said Invention for "THE IMPROVEMENT OF STOVES
FOR THE PURPOSE OF WARMING ROOMS AND BAKING BREAD, CALLED THE
'HYGEIAN STOVE,'" to be as follows:-
The said stove consists of three entirely distinct and separate parts, namely,
of two cylinders made of sheet iron, placed within each other, and a baking
tin placed on the lid of the inner cylinder.
I. The inner cylinder, marked on the Drawing in blue ink, contains the fuel,
and consists of three parts; (a), the body of the cylinder-height, 18 inches,
diameter, 7 inches; (b), a close fitting lid with nosle-diameter of the latter,
2 inches; (c), an elbow chimney, fitting on the nosle of the lid, and passing
through the outer cylinder to carry off the smoke; it tapers from 2 inches to
1inch, where it passes through the outer cylinder. By the handle hanging

page_text: down its side, the said cylinder can be removed.
The space under the grate
is the receptacle for the ashes falling through the grate. At equal distances,
one inch below the grate, there are five holes, of an inch in diameter, to
admit the air necessary to the combustion within.
II. The outer cylinder, marked on the Drawing in black ink, consists of two
parts; (d), the body of the cylinder-height, 28 inches, diameter, 12 inches;
(e), an air-tight lid. This cylinder has a perforated foot, 4 inches in height;
above the foot, in the centre of the bottom of the cylinder there is a round
hole, 2 inches in diameter, for the purpose of regulating the admission of the
outer air. Around the outside of the top of the cylinder a sand groove is
fixed, of the same depth as the rim of the lid. This groove is two-thirds
filled with sand. When the closely-fitting lid is put on it sinks into the
sand surrounding it, and by this means the escape of any air or smell is
prevented.
III. The baking tin, marked in red ink on the Drawing-height, 3 inches;
diameter, 9 inches. It is moveable, and is placed above the chimney with its
foot resting on the lid of the inner cylinder.
Power of the Stove. - When the weather is very cold it raises the
temperature of a room containing about 2,400 cubic feet of air to about 60°
Fahrenheit.
PARTICULAR ADVANTAGES OF THE HYGEIAN STOVE.
1. No decomposition or deterioration of the air, no smell in the room
warmed by the stove. 2. Extreme economy, both in fuel and labour.
4. Entire safety from danger of fire. 5. The baking
6. The stove being portable.
3. Great cleanliness.
of most excellent bread.
How, BY THE CONSTRUCTION OF THE "HYGEIAN STOVE," THESE ADVANTAGES
ARE OBTAINED, AND THEIR EFFECTS.
With regard to No. 1, the cylinder that contains the fire comes nowhere in
immediate contact with the outer cylinder, as there is everywhere an empty
space between them of at least 2 inches. Thus, the medium between the
outer and inner cylinder is nothing but heated air, and the heat so commu-
nicated to the outer cylinder is thrown out into the room, as it were, filtered
and purified without any possibility of scorching the air of the room, and the
effect is a most congenial, equal, and healthy temperature all over the room
without any smell whatever from the stove. The serious defect of a bad
smell in almost all stoves arises from smoke or gas leaking out from the fire-

page_text: box or chimney. In the "Hygeian stove" this is provided against by the lid
and chimney of the inner cylinder or fire-box being made to fit exactly. The
expansion of the iron, when heated, makes them all but air-tight, and when
once lighted, any escape of gas through the five small holes under the grate
is impossible, as the constant tendency of the fire to create a vacuum causes
a strong suction inward through these holes. But even if anything should
leak out from the lid or chimney, it only enters the air chamber or empty
space between the two cylinders from which it cannot escape, the top of the
outer cylinder being hermetically closed. A downward escape of the burnt
and vitiated air in the air chamber, through the centre hole in the bottom of
the outer cylinder, is from a similar cause equally impossible, as the suction
of the five air holes in the fire box produces also here a similar inward current
of the outer air which first mixes with the heated air in the air chamber, and
thus by being constantly absorbed and renewed again prevents its becoming
altogether vitiated. This process also acts very favorably on the air of the
room, as by continually absorbing and changing it, it contributes much to
keeping it pure and uncorrupted.
As to No. 2, I need only mention, that with one pennyworth of coal the stove
acts for at least 24 hours, keeping the room at an equal temperature the whole
time. Cause and effect in the action, or rather breathing of the stove, are so
carefully calculated that the mere influence of the outer atmosphere acts upon
the current as a kind of regulator, since in comparatively warmer weather
the combustion within is much delayed, and thus less heat is produced; but
then it continues burning from 36 to 40 hours, whilst in colder weather it
produces heat in proportion to the intensity of the cold; but, as the fire is
also proportionately intense, the fuel is sooner consumed, yet it seldom lasts
less than 24 hours. When the stove is once. lighted, it requires no farther
attention.
With regard to No. 3, the inner cylinder being moveable, can be taken out
and carried away to be emptied and re-charged; the room remains, therefore,
always free from smoke, dust, or ashes.
No. 4 is secured by the fire being so encased that an accident is quite im-
possible unless the stove be first smashed to pieces.
As to No. 5, the bread produced by the stove cannot be surpassed in
lightness, goodness, and wholesomeness.
With regard to No. 6, the stove, even when in action, can be moved"
from one room or floor to another, with the greatest ease & without
danger.

page_text: CHARGING AND LIGHTING THE SAID STOVE.
The coal required for the use of this stove must not cake, must continue
to burn without poking, and until the last cinder is consumed to ashes (best
inland coal). Good coke will also do with some of the coal mentioned. The
cylinder is first about half filled with pieces of coal, from about the size of a
nut to that of an apple; then it may be filled up to within 3 or 4 inches of
the top with small coal. A star of patent firewood is then placed in the centre
upon the coal with the resinous part downwards and around it some cinders.
It is then carried back to and replaced in the outer cylinder, close to the
side opposite its outlet for the chimney. The patent firewood is now lighted
with a bit of wood of the length of a piece of common firewood, from which
it is cut. When the star has well caught fire the lid is put on and then the
elbow, the mouth of which is fitted into the opening of the outer cylinder
by moving the inner cylinder forward into the middle of the outer one, where:
upon the whole is shut up by putting on the lid of the outer cylinder. If
there is no patent firewood to be had, a few sticks of common firewood with
a few cinders will also do, and will easily be lighted with paper placed under
them, or by putting a few burning coals upon them. When the stove is being
lighted, the regulator at the foot must be entirely open; but when the stove,
about a quarter of an hour afterwards, has become hot, the regulator ought
to be half shut at least. Should the stove, during the 24 hours, appear to
grow less hot, the regulator has only to be entirely reopened until the stove is
hot again.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Emil Ryffel in the Great Seal Patent Office on the
11th August 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
EMIL RYFFEL, of Wimbledon, in the County of Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirteenth day of February, in the year of our
Lord One thousand eight hundred and fifty-eight, in the twenty-first year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Emil Ryffel, Her special licence that I, the said John
Emil Ryffel, my executors, administrators, and assigns, or such others as
I, the said John Emil Ryffel, my executors, administrators, and assigns,

page_text: 5
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 "THE
IMPROVEMENT OF STOVES FOR THE PURPOSE OF WARMING ROOMS, BAKING BREAD
& COOKING, CALLED THE HYGEIAN STOVE," upon the condition (amongst others)
that I, the said John Emil Ryffel, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said Inven-
tion, and in 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 I, the said John Emil Ryffel, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
2
The said stove is of cylindrical form, 34 inches high, & 12 inches in
diameter; it consists of two entirely distinct parts, viz., A, the outer cylinder,
& B, the inner cylinder; C is a baking tin, 3 inches high, & 8 inches in
diameter, resting with its foot on the lid of B. Cylinder A consists of two
parts the body, & an air-tight lid. Its foot is perforated to admit the outer
air into the cylinder through the round hole a, inches in diameter, cut in the
bottom. This hole is regulated by the rod b. Around the outside of the top
of the cylinder a sand groove c is fixed, into which the rim of the lid sinks.
The nosle d is the outlet for the chimney. Cylinder B contains the fuel, &
consists of three parts. 1, the body of the cylinder-height, 18 inches;
diameter, 7 inches. 2, a close-fitting lid with nosle, 2 inches in diameter.
3, an elbow chimney, fitting on the nosle of the lid, and passing through
nosle d of the outer cylinder to carry off the smoke; it tapers from 2 inches
to 1 inch, where it passes through the outer cylinder. By the handle fixed
to the sides of the top, the said cylinder can be removed. The space under
the grate is the receptacle for the ashes falling through; its height is 3 inches.
At equal distances, 1 inch below the grate, are five holes e, of an inch
in diameter, to admit the air necessary for the combustion within.
-
Power of the Stove. When the weather is very cold it raises the
temperature of a room containing about 2,400 cubic feet of air to about
60° Fahrenheit. If the room is larger, the dimensions of the stove aro
encreased.

page_text: I ARTICULAK ADVANTAGES OF THE FLYGEIAN STOVE.
1. This stove produces a congenial, equal, & most healthy temperature all
over the room, without any decomposition of the air or any smell whatever.
2. With one pennyworth of coal it maintains this temperature for about 24
hours, & when lighted, it requires no farther attention. 3. It never causes
either dust or ashes in the room. 4. It bakes excellent bread, and can also
easily be used for cooking purposes. 5. It is portable. 6. Danger of fire in
the use of it is impossible.
How, BY THE CONSTRUCTION OF THE HYGEIAN STOVE THESE ADVANTAGES ARE
OBTAINED, AND THEIR EFFECTS.
With regard to 1: the cylinder that contains the fire comes nowhere in
immediate contact with the outer cylinder, as there is everywhere an empty
space between them of at least 2 inches. Thus, the medium between the
outer and inner cylinder is nothing but heated air, & the heat so commu-
nicated to the outer cylinder is thrown out into the room, as it were, filtered
and purified without any possibility of scorching the air in the room, & the
effect is a most congenial temperature without any smell whatever from the
stove. The serious defect of a bad smell in almost all stoves arises from
smoke or gas leaking out from the fire-box or chimney, or from the air of the
room being burnt by coming in contact with the fire-box.
In the Hygeian
stove all this is provided against by the lid & chimney of the inner cylinder
being made to fit exactly. The expansion of the iron, when heated, makes it
all but air-tight, and when once lighted, any escape of gas through the five
small holes under the grate is impossible, as the constant tendency of the fire
to create a vacuum causes a strong suction inward through these holes. But,
even if anything should leak out from the lid or chimney, it only enters
the air chamber or empty space between the two cylinders, from which
it cannot escape, the top of the outer cylinder being hermetically closed. A
downward escape of the burnt and vitiated air in the air chamber, through the
centre hole a in the bottom of the outer cylinder is from a similar cause
equally impossible, as the suction of the five air holes e produces also here a
similar inward current of the outer air which first mixes with the heated air
in the air chamber, and thus, by being constantly absorbed & renewed again,
prevents its becoming altogether vitiated. This process also acts very favorably
on the air of the room, as by continually absorbing & changing it, it contributes
much to keeping it pure & uncorrupted.

page_text: As to 2: it need only be mentioned, that with one pennyworth of coat the
tove acts for at least 24 hours, keeping the room at an equal temperature during
he whole time. Cause & effect in the action of the draught, or rather breathing
of the stove, are so carefully calculated, that the mere influence of the outer
tmosphere acts upon the current as a kind of regulator, since in comparatively.
varmer weather the combustion within is much delayed, and thus less heat is
produced; but then it continues burning from 36 to 40 hours, whilst in colder
weather it produces heat in proportion to the intensity of the cold; but as the
fire is also proportionately intense, the fuel is sooner consumed, yet it seldom
asts less than 24 hours. The stove once lighted, continues burning without
farther trouble.
With regard to 3: the inner cylinder being moveable, can be taken out
& carried away to be emptied and re-charged. The room therefore remains
always free from smoke, dust, or ashes.
4, is secured by the fire being so incased that an accident is quite impossible
unless the stove be first smashed to pieces.
As to 5 the bread produced by the stove cannot be surpassed in lightness,
goodness, and wholesomeness.
With regard to 6: the stove, even when in action, can be removed from
one room or floor to another with the greatest ease & without danger. To
persons who suffer either from rheumatism, defective circulation of the blood,
chilblains, cold feet, &c., the stove will be an invaluable acquisition. It is
particularly suited for parlours, studies, offices, smaller dining & breakfast
rooms, bed rooms, dressing rooms, & nurseries, and also for halls & green-
houses; in fact, the dimensions of the stove can be altered to suit rooms of
any size. On precisely the same principles a stove merely for baking and cook-
ing purposes has been constructed by the Inventor; only, in order to gain
more space, the apparatus has a horizontal instead of a perpendicular position,
which allows about four loaves to be baked at the same time instead of but one.
DIRECTIONS FOR USING THE STOVE.
First, half fill the sandgroove c with fine dry sand, so that the rim of the
lid sinks about an inch into it. If placed before a chimney, a chimney-board
is required. Coal that cakes cannot be used; best inland coal (Stoneyford's)
answers very well; good coke mixed with it will also do. In charging the
5 stove, fill the space f, g, of cylinder B up to within 4 inches of the top, taking
care to put only whole pieces on the grate, and for about 6 inches above it;
then place a star of patent firewood in the centre upon the coal, surround it
with some cinders, so that they reach a little above the star, but the centre

page_text: must be kept free; now place cylinder B' into: cylinder A, light the star,
then put the lid gently on; and afterwards the elbow, the end of which is fitted
into the hole for the chimney by moving cylinder B forward into the centre of
cylinder A, which you then close with the lid. The regulator a. at the foot
must at first be entirely open. When the stove has become quite hot, it may
be half shut. It is necessary for the control of the fire that the chimney
should be so narrow; therefore the lid & elbow on cylinder B, and the nosle
and tube of cylinder A must be freed from soot every time the stove is
emptied.
In witness whereof, I, the said John Emil Ryffel; have heretofore set my
hand & sool this 11th
(L.S.) JOHN EMIL RYFFEL.