e temperatures,
humidities, and air circulation properly manipulated, there should be
complete success in the handling of this type of dry kiln.

The Progressive type of dry kiln is adapted to such lines of
manufacture that have large quantities of material to kiln-dry where
the species to be dried is of a similiar nature or texture, and does
not vary to any great extent in its thickness, such, for instance, as:

Oak flooring plants;
Maple flooring plants;
Cooperage plants;
Large box plants;
Furniture factories; etc.

In the selection of this kind of dry kiln, consideration should be
given to the question of ground space of sufficient length or
dimension to accommodate a kiln of proper length for successful
drying.

The "Apartment" Dry Kiln

The Apartment system of dry kilns are primarily designed for the
drying of different kinds or sizes of material at the same time, a
separate room or apartment being devoted to each species or size when
the quantity is sufficient (see Fig. 36).

These kilns are sometimes built single or in batteries of two or more,
generally not exceeding 40 or 50 feet in length with doors and
platforms at both ends the same as the Progressive kilns; but in
operation each kiln is entirely filled at one loading and then closed,
and the entire contents dried at one time, then emptied and again
recharged.

Any number of apartments may be built, and each apartment may be
arranged to handle any number of cars, generally about three or four,
or they may be so constructed that the material is piled directly upon
the floor of the drying room.

[Illustration: Fig. 36. Exterior View of Six Apartment Dry
Kilns, each 10 Feet wide by 52 Feet long, End-wise Piling.
They are entirely of fire-proof construction and equipped
with double doors (Hussey asbestos outside and canvas
inside), and are also equipped with humidity and air control
dampers, which may be operated from the outside without
opening the kiln doors, which is a very good feature.]

When cars are used, it is well to have a transfer car at each end of
the kilns, and stub tracks for holding cars of dry material, and for
the loading of the unseasoned stock, as in this manner the kilns may
be kept in full operation at all times.

In this type of dry kiln the material receives the same treatment and
process that it would in a Progressive kiln. The advantages of
Apartme