porters deliver the pouches and sacks into the car, the label of each
being scanned and checked by the clerks, to detect if all connections
due are received, and that no mail may be delayed by being carried out
on the road with the other mail and returned. The last pouch is scarcely
received, when a sudden, but not violent, shock announces that the
locomotive is attached to the train, and the start about to be made. The
sound of the gong, seconded by the electrifying and resonant "Aboard!"
of the conductor, and the post-office on wheels is under way. Now, all
is a scene of bustle, but not confusion. The two clerks, to whom are
assigned the duty of distributing direct packages of letters and
newspaper mail, including merchandise, deftly empty the pouches, out of
which pour packages of letters and circulars, to be distributed unbroken
into pouches, and others labeled to this route and different States,
which are in turn to be separated into packages by routes, States, and
large towns, at the letter-case. To the clerk in charge is assigned the
sorting of such letters as are destined to distant routes or terminal
connecting lines; and his associate, or second clerk, is busy
distributing letter mail for local delivery, and into separations for
intermediate connections.

In addition to sorting letters, the clerk in charge has charge of the
registered mail, which requires special care in its reception and
delivery, booking and receipting therefor. Large pouches of registered
mail are also placed in his charge, _en transit_ between large
cities, and represent great value. The peculiar tooting of the whistle,
or a peculiar movement of the train around a curve, warns the fourth
clerk, who is on the alert, of a "catch" station; the letter mail for
that post-office is quickly deposited by the local clerk in the pouch,
the lock is snapped, and he is standing at the door not a minute too
soon or too late; the pouch is thrown out at a designated spot and one