em."

"Then, besides," continued the surgeon, "if the men strike the bells
themselves, the sound, coming regularly every half hour, proves that
they are at their posts and attending to their duties. So that, even if
a machine could be invented to strike the time on board ship ever so
truly, I do not think they would like to adopt it.

"Another difference in striking the time on board ship," continued the
surgeon, "is, that they strike it by half hours instead of by hours.
Scarcely any of the ship's company have watches. In fact, watches are of
very little use at sea, the time is so continually changing from day to
day. The sailors, therefore, and nearly all on board, depend wholly on
the bells; and it is necessary, accordingly, that they should be struck
often. Every two bells, therefore, means an hour; and a single bell at
the end means half an hour. Now, I will strike the bells for you, and
you may tell me what o'clock it is. We begin after twelve o'clock.

"Ding!"

"Half past twelve," said Rollo.

"Ding--ding!" said the surgeon again, imitating the sound of the bell
with his voice.

"One o'clock," said Rollo.

"Ding--ding! Ding!" said the surgeon.

"Half past one o'clock."

"Ding--ding! Ding--ding!"

"Two o'clock!"

"Ding--ding! Ding--ding! Ding!"

"Half past two."

"Ding--ding! Ding--ding! Ding--ding!"

"Three!"

"Ding--ding! Ding--ding! Ding-ding! Ding!"

"Half past three."

"Ding--ding! Ding--ding! Ding--ding! Ding--ding!"

"Four o'clock."

"Yes," said the surgeon, "that is eight bells, and that is the end. Now
they stop and begin again with one bell, which means half past four; and
so they go on to eight bells again, which makes it eight o'clock. The
next eight bells is twelve o'clock at night, and the next is at four
o'clock in the morning, and the next at eight o'clock. So that eight
bells means four o'clock, and eight o'clock, and twelve o'clock, by day;
and four o'clock, and eight o'clock, and twelve o'clock, by night."

"Yes," said Rollo, "now I understand it."

"Eight bells is a very important striking," continued the surgeon. "It
is a curious fact, that almost every thing important that is done at sea
is done at some eight bells or other."

"How is that?" asked Rollo.

"Why, in the first place," replied the surgeon, "at eight bells in the
morning, the gong sounds to wake the passengers up. Then the watch
changes, too; that is, the set of men that have been on deck and had
c