The external radiation is regulated by the use of nonconducting plaster
applied to the flue-plate and to the sides of the corner-flues, so
that the heat is prevented from radiating in any direction except
toward the oven. The doors, sides, and bottom of the stove are lined
with tin casings, which hold a stratum of air, also a non-conductor.
These are so arranged as to be removed whenever the weather becomes
cold, so that the heat may then radiate into the kitchen. The outer
edges of the oven are also similarly protected from loss of heat by
tin casings and air-spaces, and the oven-doors opening at the front
of the store are provided with the same economical savers of heat.
High tin covers placed on the top prevent the heat from radiating above
the stove. These are exceedingly useful, as the space under them is
well heated and arranged for baking, for heating irons, and many other
incidental necessities. Cake and pies can be baked on the top, while
the oven is used for bread or for meats. When all the casings and
covers are on, almost all the heat is confined within the stove, and
whenever heat for the room is wanted, opening the front oven-doors
turns it out into the kitchen.

Another contrivance is that of ventilating-holes in the front doors,
through which fresh air is brought into the oven. This secures several
purposes: it carries off the fumes of cooking meats, and prevents the
mixing of flavors when different articles are cooked in the oven; it
drives the heat that accumulates between the fire-box and front doors
down around the oven, and equalizes its heat, so that articles need
not be moved while baking; and lastly, as the air passes through the
holes of the fire-box, it causes the burning of gases in the smoke,
and thus increases heat. When wood or bituminous coal is used,
perforated metal linings are put in the fire-box, and the result is