e Monarch Telephone Manufacturing Company, with the
result shown in Fig. 54. The construction in this case is not unlike
that of an ordinary permanent-magnet receiver, except that in the
place of the permanent magnets two soft iron cores _1-1_ are employed.
On these are wound two long bobbins of insulated wire so that the
direct current flowing over the telephone line will pass through these
and magnetize the cores to the same degree and for the same purpose as
in the case of permanent magnets. These soft iron magnet cores _1-1_
continue to a point near the coil chamber, where they join the two
soft iron pole pieces _2-2_, upon which the ordinary voice-current
coils are wound. The two long coils _4-4_, which may be termed the
direct-current coils, are of somewhat lower resistance than the two
voice-current coils _3-3_. They are, however, by virtue of their
greater number of turns and the greater amount of iron that is
included in their cores, of much higher impedance than the
voice-current coils _3-3_. These two sets of coils _4-4_ and _3-3_ are
connected in multiple. As a result of their lower ohmic resistance the
coils _4-4_ will take a greater amount of the steady current which
comes over the line, and therefore the greater proportion of the
steady current will be employed in magnetizing the bar magnets. On
account of their higher impedance to alternating currents, however,
nearly all of the voice currents which are superposed on the steady
currents, flowing in the line will pass through the voice-current
coils _3-3_, and, being near the diaphragm, these currents will so
vary the steady magnetism in the cores _2-2_ as to produce the
necessary vibration of the diaphragm.

[Illustration: Fig. 54. Monarch Direct-Current Receiver]

This receiver, like the one of the Automatic Electric Company, does
not rely on the shell in any respect to maintain the permanency of
relation between the pole pieces and the diaphragm. The cup _5_, which
is of pressed brass, contains the voice-current coils and also acts as
a seat for the diaphragm. The entire working parts of this receiver
may be removed by merely unscrewing the ear piece from the hard rubber
shell, thus permitting the whole works to be withdrawn in an obvious
manner.

Dean Receiver. Of such decided novelty as to be almost revolutionary
in character is the receiver recently put on the market by the Dean
Electric Company and shown in Fig. 55. This receiver is of the
dire