ounted the group of
switch springs by which the circuit changes of the instrument are
brought about when the hook is raised or lowered. The spring _8_ is
longer than the others, and projects upwardly far enough to engage the
lug on the switch-hook lever _2_. This spring, which is so bent as to
close the contacts at the right when not prevented by the switch
lever, also serves as an actuating spring to raise the lever _2_ when
the receiver is removed from it. This spring, when the receiver is
removed from the hook, engages the two springs at the right, as shown,
or when the receiver is placed on the hook, breaks contact with the
two right-hand springs and makes contact respectively with the
left-hand spring and also with the contact _9_ which forms the
transmitter terminal.

[Illustration: Fig. 86. Desk-Stand Hook Switch]

It is seen from an inspection of this switch hook that it has two make
and two break contacts. The various contact springs are connected with
the several binding posts shown, these forming the connectors for the
flexible cord conductors leading into the base and up through the
standard of the desk stand. By means of the conductors in this cord
the circuits are led to the other parts of the instrument, such as the
induction coil, call bell, and generator, if there is one, which, in
the case of the Western Electric Company's desk set, are all mounted
separately from the portable desk stand proper.

This hook switch is accessible in an easy manner and yet not subject
to the tampering of idle or mischievous persons. By taking out the
screw _7_ the entire hook switch may be lifted out of the tube forming
the standard, the cords leading to the various binding posts being
slid along through the tube. By this means the connections to the hook
switch, as well as the contact of the switch itself, are readily
inspected or repaired by those whose duty it is to perform such
operations.

_Kellogg._ In Fig. 87 is shown a sectional view of the desk-stand hook
switch of the Kellogg Switchboard and Supply Company. In this it will
be seen that instead of placing the switch-hook springs within the
standard or tube, as in the case of the Western Electric Company, they
are mounted in the base where they are readily accessible by merely
taking off the base plate from the bottom of the stand. The hook lever
operates on the long spring of the group of switch springs by means of
a toggle joint in an obvious manner. This sw