g the
subscribers, that being automatically taken care of when they hang up
their receivers at the close of the conversation.

From the foregoing it will be seen that there is this fundamental
difference between the automatic and the automanual--the automatic
system dispenses entirely with the central-office operator for all
ordinary switching functions; the automanual employs operators but
attempts to so facilitate their work that they may handle very many more
calls than would be possible in a manual system, and at the same time
secures the advantages of secrecy which the automatic system secures to
its subscribers.

=Subscriber's Apparatus.= One of the main points in the controversy
concerning automatic _versus_ manual systems is whether or not it is
desirable to have the subscriber ask for his connection or to have him
make certain simple movements with his fingers which will lead to his
securing it. The developers of the automanual system have taken the
position that the most desirable way, so far as the subscriber is
concerned, is to let him ask for it. It is probable that this point
will not be a deciding one in the choice of future systems, since it
already seems to be proven that the subscribers in automatic systems are
willing to go through the necessary movements to mechanically set up the
call. The advantage which the automanual system shares with the manual,
however, in the greater simplicity of its subscriber's station
apparatus, cannot be gainsaid.

[Illustration: Fig. 405. Operators' Key Tables]

[Illustration: Fig. 406. Top View of Key Table]

=Operator's Equipment.= The general form of the operator's equipment is
shown in Fig. 405. A closer view of the top of one of the key tables is
shown in Fig. 406. As will be seen, the equipment on each operator's
position consists of three separate sets of push-button keys closely
resembling in external appearance the keys of a typewriter or adding
machine. Immediately above each set of keys are the signal lamps
belonging to that set.

The operator's keys are arranged in strips of ten, placed _across_
rather than _lengthwise_ on the key shelf. One of these strips is shown
in Fig. 407. There are as many strips of keys in each set as there are
digits in the subscribers' numbers, _i. e._, three in a system having a
capacity of less than one thousand; four in a system of less than ten
thousand; and so on. In addition to the number keys of each set is a
partial