rator's position. A ticket tube connects this valve with a
distributing table at or near which the tickets are written. The tickets
are of uniform size and are so made as to enable a flap to be bent up
easily along one edge. The distributing operator has merely to insert
the ticket, bent edge foremost, in the open end of the tube, whereupon
the air pressure behind it will drive it through to its destination,
near by or far away. The tickets travel thirty feet a second. The tube
may be bent into almost any required form. The ticket, on arriving at a
line operator's position, slides between two springs, breaking a shunt
around a relay and allowing the latter to light the lamp.

=Waystations.= Waystations on long-distance lines may be equipped in
several ways. Most of them have magneto sets and can ring each other.
Some are equipped with common-battery sets and get all current for
signaling and transmission from a terminal central office. In the latter
case, there is the advantage that the ringers are in series with
condensers, assisting greatly in tests for fault locations. Such tests
are hindered by the presence of ringer bridges across the line, as in
magneto practice. Condensers can be inserted in series with ringers of
magneto sets if the testing advantage is valued highly enough. A
disadvantage of the use of common-battery sets in waystations on
long-distance lines is the lessened transmission volume of the stations
farthest from the current source.

_Center Checking._ An operating advantage of common-battery sets on
long-distance lines is that all calls are forced to be answered by the
terminal station. Waystations can not call each other, as they have no
calling means. With magneto sets, waystation agents sometimes call each
other direct and neglect to record the call and to remit its price. When
they can not call each other direct, the revenues of the company
increase.

A traffic method which requires all calls from waystations to be made to
a central switching office is called a center-checking system. It is so
called because all checking for stations so switched is done at the
central point instead of each waystation keeping its own records of
calls sent and received. In such practice it is usual to bill each
station once a month for the messages it sent. Where center checking is
not practiced, the agent makes a report and sends a remittance. Center
checking comes about naturally for waystations having no ring