They are tickets, of course," replied Norwood.

"I don't think so," added the captain. "All the people seem to throw
them away, and the floor of the car is covered with them."

"O, I know now what they are!" exclaimed Norwood. "I have heard of
such things."

"I never did."

"I suppose you know what 'knocking down' means--don't you?" laughed
the second lieutenant.

"It means stealing."

"Precisely so. It is said that conductors and omnibus drivers at home
'knock down' a good deal, which is the technical name for taking a
portion of the fares. They use 'spotters' in our country to keep the
conductors and drivers honest."

"Spotters?"

"Yes, that's the name of them. They are men and women, whom the
conductors cannot distinguish from other passengers, employed by the
railway companies to ride in the cars, and report the number of
passengers on certain trips, so that the agents can tell whether the
fares are all paid over. These tickets are used for the same purpose."

"I don't see what good they do. They certainly can't keep the men
honest, for almost everybody throws away his ticket."

"They are called control-marks," said a gentleman next to the captain,
who had been listening with interest to the conversation, and who
spoke good English. "The man has to tear one of them off every time a
passenger pays him."

"They are all numbered, I see; mine is nine hundred and four," added
Lincoln.

"When the man gives up this roll at night, the next number will show
how many he has torn off. If he began at No. 200 this morning, he has
taken seven hundred and four fares."

"But he might neglect to tear off fifty or a hundred in the course of
a day," suggested Lincoln, "and put the money for them in his pocket."

"If he does so, everybody is watching him, and anybody may report him
to the agent. I am a share-owner of the company, and for aught the
conductor knows, there may be one in every car. If the man neglects
his duty, my interest would prompt me to look after him."

"I see; thank you, sir."

"Here is Tivoli," added the gentleman. "I suppose you are going
there."

"Yes, sir."

"It is a fine garden, and very cheap."

The young officers left the car, and bought tickets at the gate, for
which they paid one mark, or nine cents, each. Near the entrance they
found a man selling programmes of the evening's entertainment, at two
skillings each. Captain Lincoln bought one, for he carefully preserved
every handbil