The children were sure they would not get too tired, and a little later
they all got out at the subway station at Brooklyn Bridge.

There were many persons hurrying to and fro, trains coming in and going
out, and lights all over, making the children think it was night, though
it was in the morning.

"Wait here just a minute," said Mr. Bobbsey, showing the twins a less
crowded place where they could stay. "I want to get a magazine over at the
news-stand," he added.

The magazine he wanted had been put away under a pile of papers, and as
the boy was getting it out Flossie caught sight, down the platform, of a
man pasting up on the advertising boards in the underground station, some
new posters.

"Oh, maybe it's signs about a circus, Freddie!" cried the little girl
"Come on and watch!"

Freddie was always ready to go, and he had darted off after his sister
down the long platform before Bert and Nan saw them. When the two older
children missed the younger twins they looked hurriedly about for them.

"There they are--watching that bill-poster," said Bert. For the
underground subway stations are much used by advertisers, gaily colored
sheets of paper being pasted on boards put there for that purpose.

"You mustn't run away like that!" said Nan to Flossie, as she came up to
her sister, to lead her back.