ll the parts in so confined a
space. This interferes somewhat with the accessibility of the various
parts, but great ingenuity has been manifested in making the parts
readily get-at-able in case of necessity for repairs or alterations.

[Illustration: Fig. 154. Steel Box Hotel]

[Illustration: Fig. 155. Steel Box Hotel Set]

_Desk_. The common-battery desk telephone presents a somewhat simpler
problem than the magneto desk telephone for the reason that the
generator and local battery, the two most bulky parts of a magneto
telephone, do not have to be provided for. Some companies, in
manufacturing desk stands for common-battery purposes, mount the
condenser and the induction coil or impedance coil, or whatever device
is used in connection with the talking circuit, in the base of the
desk stand itself, and mount the polarized ringer and the condenser
used for ringing purposes in a separate bell box adapted to be
mounted on the wall or some portion of the desk. Other companies mount
only the transmitter, receiver, and hook switch on the desk stand
proper and put the condenser or induction coil, or other device
associated with the talking circuit, in the bell box. There is little
to choose between the two general practices. The number of conducting
strands in the flexible cord is somewhat dependent on the arrangement
of the circuit employed.

[Illustration: Fig. 156. Common-Battery Desk Set]

[Illustration: Fig. 157. Bell for Common-Battery Desk Set.]

The Kellogg Switchboard and Supply Company is one which places all the
parts, except the polarized ringer and the associated condenser, in
the desk stand itself. In Fig. 156 is shown a bottom view of the desk
stand with the bottom plate removed. In the upper portion of the
circle of the base is shown a small condenser which is placed in the
talking circuit in series with the receiver. In the right-hand portion
of the circle of the base is shown a small impedance coil, which is
placed in series with the transmitter but in shunt relation with the
condenser and the receiver.

[Illustration: Fig. 158. Bell for Common-Battery Desk Set]

In Figs. 157 and 158 are shown two views of the type of bell box
employed by the Kellogg Company in connection with the common-battery
desk sets, this box being of pressed-steel construction and having a
removable lid, as shown in Fig. 158, by which the working parts of the
ringer are made readily accessible, as are also the terminals for