AN IMPROVED INCUBATING APPARATUS
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by the said May Arnold at the Office
of the Commissioners of Patents on the 4th June 1880.
MAY ARNOLD, of Acton, in the County of Middlesex, Spinster. "AN IMPROVED
INCUBATING APPARATUS."
Whereas in the usual methods of hatching by hot water only as the source of
heat the eggs are subjected to motion bi-daily at the times of cooling, which is
contrary to nature, or, if not so subjected, are either insufficiently cooled or the
heat inconveniently reduced at its source, according to the present Invention the
eggs remain undisturbed at cooling times, as in the natural nest when the hen
leaves it, yet the application of cooling air at such times is so abundant as to
diminish the time necessary for the operation, and the consequent over-cooling of
the hot water tank likewise. And whereas in the usual inethods of artificial
incubation no heat is applied below, which is contrary to nature, the bottom of the
nest amongst the eggs becoming as hot as the hen's feet and breast, in the present
Invention a constant slight heat is maintained below the eggs. And whereas most
egg receptacles of incubators have a level floor, in this Invention the floor slopes
all ways to the centre, which admits of damping the material of the nest without
exaggeration, and of collecting a small body of the damping water, which forms a
constantly evaporating surface within the incubator to assist in safely preventing
the overdrying of the shell's membrane.
To effect these objects the shape of a baker's brick oven is adopted, the sides,
however, being elongated beyond the usual proportions of such an oven in order to
admit a larger number of eggs. This oven has a removable door in the usual place,
in which door is contained a glass for the due observation of the thermometer
within, without necessarily opening the said door, and through which door a
removable ventilating pipe passes. There is also a large ventilating pipe at the
back of the oven interior. Round the oven interior there is a hot water tank and

page_text: hollow jacket filled with non-conducting material properly constructed for main-
taining the interior heat with the smallest daily addition of hot water. This tank
and jacket may be of any shape above and at the sides of the oven, but it is a
special feature of this Invention that the hot water tank also follows the form of
the sloping floor of the oven above described at a narrow interval below the said
floor, supplying a certain heat there which is modified by a sheet of cork or
"corticine" placed above the said floor, and also by the sand and straw laid thereon
to form the nest.
The interior, with its oven-like form, door, floor sloping to a centre, and the
arrangement of the ventilating pipes, are the only points of this new Invention
which it is desired to protect by Letters Patent. It will serve either as an incubator
proper or for the preservation of the young chicks for a few days after birth, as
does the natural nest.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, and
of an Order of the Lord Chancellor, filed by the said May Arnold in the
Great Seal Patent Office on the 17th December 1880.
MAY ARNOLD, of Acton, in the County of Middlesex, Spinster. "AN IMPROVED
INCUBATING APPARATUS."
My Invention relates to incubating apparatus. It is not an improvement merely
on other incubators; it follows them only in procuring the heating power by
carrying water from a separate source, and not creating it by fire or flame within
the apparatus itself. My Invention differs from all other hot water incubators in
this particular, that the eggs for hatching are placed in a hollow dry space in the
interior of the hot water tank itself, which is horizontally pierced so that one end
thereof is towards the breast of the person attending to the hatching process. In
this hollow space the eggs remain from the first of the twenty one days of incuba-
tion to the last. It is indifferent whether the form of this hollow space be
ovenshaped, oval, circular, rectangular, or otherwise. In the usual methods of
hatching by hot water only as the source of heat the eggs are subjected to motion
bi-daily at times of cooling, which is contrary to nature, or, if not so subjected,
are either insufficiently cooled or the heat is inconveniently reduced at its source.
According to the present Invention the eggs remain undisturbed at cooling times,
as in the natural nest when the hen leaves it; yet, in spite of the continued
presence of the hot water tank about them, the application of cooling air at such
times is so sudden and abundant as to diminish the time necessary for the
operation and the consequent overcooling of the hot water tank likewise. The
tank of my Invention is assisted by the hot water circulating round the egg-
chamber in recovering the heat of the latter rapidly when said tank is refilled
and the apparatus reclosed. In the usual methods of hot-water-incubation no heat
is maintained below, which is contrary to nature (the bottom of the natural nest,
from its non-conducting lining and also its remaining stationary in a usually
sheltered spot, retaining much heat communicated from the hen's breast and feet
even during the period of her absence). In the present Invention a similar modified
heat is maintained below the eggs, not only during incubation, but even during the
said period of cooling, counteracting the liberal admission of cooling air to them,
its continued maintenance being rendered desirable by the fact that the said air is
admitted in a strong rush or current. Most egg-receptacles of incubators have a
level floor. In the present Invention the floor slopes always to the centre, which
admits of damping the material of the nest without exaggeration, and collecting a
small body of the damping water in a central cup, which forms a constantly
evaporating surface within the incubator to assist in safely preventing the over-
drying of the shell's membrane. To effect these objects the shape of a baker's
brick oven is one of those shapes suitable for the egg-chamber, the sides however
being elongated beyond the usual proportions of such an oven in order to admit a
large number of eggs. This chamber has a removable door in the usual place of
an oven door, which is equal in extent to the whole mouth of the chamber
containing the eggs, and contains a glass for the due observation of the thermometer
within the aforesaid chamber, without necessarily opening said door, through which
a removable ventilating plug passes. There is also a large ventilating pipe
capable of being entirely open, entirely closed, or affording modified ventilation by
the use of a secondary plug through its stopper at the back of the interior of said
chamber. Round said interior there is a hot water tank and a hollow jacket filled
with non-conducting material of a powerful character, properly constructed for
maintaining the interior heat with the smallest daily addition of hot water, and

page_text: round the jacket a wooden case with its own door forming a second opposite the
wooden door or closed mouth of the egg-cavity or nest, through which the extremity
of the air plug in the latter passes. This tank, tank-cavity, and jacket may be of
any shape above and at the sides of the egg-chamber provided the tank be
penetrated longitudinally (not vertically with an open top), but it is a special
feature of this Invention that an increasingly narrow portion of the hot water tank
is contained below the sloping floor of the aforesaid egg-chamber containing the
least hot water where the animal heat of the growing vitality within the collected
eggs is greatest, thus supplying a certain heat there which is modified by a sheet of
cork or corticine placed above the said floor, and also by the sand and straw laid
thereon to form the nest. My Invention will serve either as an incubator proper
or for the preservation of the young chicks for a few days after birth, as does the
natural nest.
For the better explanation and illustration of my said Invention I refer to the
accompanying Drawings, in which the same letters designate the same parts.
Figure 1 is a perspective view of my Invention on a stand, which stand however
forms no part of my Invention. Figure 2 is a longitudinal section of my improved
incubating apparatus at the line A, B, on Figure 1; Figure 3 is a transverse
section of said apparatus at line C, D, Figure 1.
I provide a case a, preferably of wood, pyramidal in shape, but with a flat top.
The parts of this case are fastened together by screws, for more convenient
occasional repair, inserted so as to cross the grain of the wood, as shewn in Figure 2.
By always inserting the screws in such a way as to cross the grain of at least one
of the pieces to be so joined together I secure the necessary degree of strength in
the finished case without having to resort to the use of outside bands or corner
plates. I provide a covering a¹, of metal or other equivalent, to keep off any hot
water that may escape during filling from the funnel or entrance pipe from
penetrating the jacket. This piece of metal is folded over and protects all the
upper joints of the woodwork of the case, and is made easily removable for repairs.
In said case I place a hot water tank b, made of zinc or other suitable metal, and
supported on bearers c, and elsewhere stayed or supported as may be required.
Tubular openings for the purpose of pouring water into and drawing water off
from said tank b are shewn at d and e. The hatching chamber f is shown in
Figures 2 & 3. At the bottom of said chamber is a layer of sand f¹ and a layer of
chaff, the former to allow moisture to find its way through a ring of holes g
formed in a sliding tube h fitting in a circular well i, and the latter, the chaff, to
allow air for chickens hatched downwards to breathe. Access to this chamber is
afforded by a door of wood j, removable by two knobs k, k. It is cut on the bevil,
as shewn in Figure 2. A pane of glass 7, which may or may not be again covered
by a closely fitting square of non-conducting cork, is inserted in said door. A
thermometer m stands on the sand just within the door, and shows the heat
obtaining in the hatching chamber f. A shutter n, with two cavities k¹, k', for the
purpose of receiving the knobs k, k, and a perforation 8, to enable it to pass over
the ventilating plug r, swings in a frame n¹ screwed to the front of the case. The
ventilation of the chamber f in all ordinary temperatures is provided for by two
wooden plugs perforated in a peculiar manner; one of these o fits by means of a
cork ferule q in a pipe p passing through the hot water tank b, and continued
outwards, as shown in Figure 2, and thereby opening up a communication between
the hatching chamber f and the outer air. Another ventilating plug r, of like
formation and perforation, fits in the door j. The outer end of its perforation is so
situate as not to be closed by the side of the perforation in the shutter n when the
latter is closed. The perforation o' of this plug is branched out towards the surface
of the shank of the plug, as shown, for the purpose of effecting a more equable
distribution of the atmospheric current passing through it. A layer of "Patent
silicate cotton" t, or equivalent non-conductor, placed between the case a and the
hot water tank b, prevents the temperature of the outer air from interfering with

page_text: the interior of the apparatus and also prevents the escape of heat. The metal of
the hot water tank 6 is secured safely and well at all openings in the case a, viz.,
at d, e, j, p.
Seeing that every projection in the way of pipe-head or plug of metal tends to
lead away and disperse the interior heat of the apparatus, I make every projection
(in the way of pipe or plug-head) from the apparatus (except the emptying tap) of
wood. They are in fact wooden cylinders, and the heat thereby saved to the
apparatus is considerable.
Having now fully described the nature of my Invention, and the means by
which it is to be carried into effect, I wish it to be understood that what I
consider new and therefore secured to me by the above in part recited Letters
Patent is,―
1st. In an incubator the hollow dry space of an ovenshaped, oval, circular,
rectangular, or other form in the interior of the hot water tank, as and for the
purpose hereinbefore described and illustrated in the accompanying Drawings.
2ndly. In an incubator the floor of the egg chamber so constructed as to slope to
the centre, substantially as and for the purpose herein before described and illustrated
in the said Drawings.
3rdly. In an incubator the cup placed centrally in the floor of the egg-chamber,
substantially as and for the purpose hereinbefore described and illustrated in the
said Drawings.
4thly. In an incubator the arrangement in combination of tank, tank cavity,
and jacket, substantially as and for the purpose hereinbefore described and illustrated
in the said Drawings.
5thly. The arrangements for ventilating an incubator, substantially as and for
the purpose herein before described and illustrated in the said Drawings.
6thly. The wooden projections in the way of pipe or plug-head (except the
emptying tap) in an incubator, substantially as and for the purpose herein before
described and illustrated in the said Drawings.
In witness whereof, I, the said May Arnold, have hereunto set my hand and
seal, this Fifteenth day of December, in the year of our Lord One
thousand eight hundred and eighty.
Signed and sealed in
presence of
P. O'HALLORAN,
Patent Agent,
28, Southampton Buildings,
Chancery Lane, E.C.
MAY ARNOLD. (L.S.)