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:-- 379 663 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 I'll give you another. I'm so glad you like the railway. Only, please, you mustn't walk on the line.” “Not if we face the way the train's coming?” asked Peter, after a gloomy pause, in which glances of despair were exchanged. “No--really not,” said Mother. Then Phyllis said, “Mother, didn't YOU ever walk on the railway lines when you were little?” Mother was an honest and honourable Mother, so she had to say, “Yes.” “Well, then,” said Phyllis. “But, darlings, you don't know how fond I am of you. What should I do if you got hurt?” “Are you fonder of us than Granny was of you when you were little?” Phyllis asked. Bobbie made signs to her to stop, but Phyllis never did see signs, no matter how plain they might be. Mother did not answer for a minute. She got up to put more water in the teapot. “No one,” she said at last, “ever loved anyone more than my mother loved me.” Then she was quiet again, and Bobbie kicked Phyllis hard under the table, because Bobbie understood a little bit the thoughts that were making Mother so quiet--the thoughts of the time when Mother was a little girl and was all the world to HER mother. It seems so easy and natural to run to Mother when one is in trouble. Bobbie understood a little how people do not leave off running to their mothers when they are in trouble even when they are grown up, and she thought she knew a little what it must be to be sad, and have no mother to run to any more. So she kicked Phyllis, who said:-- “What are you kicking me like that for, Bob?” And then Mother laughed a little and sighed and said:-- “Very well, then. Only let me be sure you do know which way the trains come--and don't walk on the line near the tunnel or near corners.” “Trains keep to the left like carriages,” said Peter, “so if we keep to the right, we're bound to see them coming.” “Very well,” said Mother, and I dare say you think that she ought not to have said it. But she remembered about when she was a little girl herself, and she did say it--and neither her own children nor you nor any other children in the world could ever understand exactly what it cost her to do it. Only some few of you, like Bobbie, may understand a very little bit.