He gave them each an orange, and promised to take them up into the signal-box one of these days when he wasn't so busy.

Several trains went through the station, and Peter noticed for the first time that engines have numbers on them, like cabs.

"Yes," said the Porter, "I knowed a young gent as used to take down the numbers of every single one he seed, in a green note-book with silver corners it was, owing to his Father being very well to do in the wholesale stationary."

Peter felt that he could take down numbers, too, even if he was not the son of a wholesale stationer. As he did not happen to have a green leather note-book with silver corners, the Porter gave him a yellow envelope and on it he noted:—

and felt that this was the beginning of what would be a most interesting collection.

That night at tea he asked Mother if she had a green leather note-book with silver corners. She had not; but when she heard what he wanted it for she gave him a little black one.

"It has a few pages torn out," said she; "but it will hold quite a lot of numbers, and when it's full