This is a story of three children, Roberta, Phyllis, and Peter, who live in a respectable suburban villa with a wonderful mother and father and a cook and servants, until one day great disgrace and poverty befalls them. Father is taken away to prison (but they do not know this at first), and they have to move to a poor cottage in the country near a railway line. Mother writes stories to earn what little they live on and they get used to being poor and have to learn not to steal coal from the railway station, even if they have so little to keep warm by. Sometimes they argue and have crises, as one does, but in time they make many new friends, and amusing adventures aplenty happen near the railway and the canal. They develop the habit of waving to the train as it goes past and sometimes the people in the coaches wave back. Their friendly habits makes them one special friend in particular, who although he mostly just goes by in the train, eventually gets to know them, and helps them out in various ways. And somehow all the good things that they do add up together and end up coming back to them, and there is happy ending to it all.
Roberta, Peter, and Phyllis are London schoolchildren aged 12, 10, and 8, respectively. One day their father leaves with two men and does not come back, and mother packs them off to a small house in the country. The kids become familiar with the passing trains, the workers at the train station and signal-box, and life in a small town while their mother struggles to make ends meet writing stories. They have various adventures -- stopping a train when a landslide covers the tracks, preventing a scraggly and penniless foreigner from arrest and taking him home, saving an infant and dog from a barge canal on fire, finding an injured older boy in the train tunnel and getting help -- while the mystery of their father's disappearance and the war between Russia and Japan percolates in the background. Sweet, charming, and imbued with all the author's wisdom and skill, this 1906 book is a gem for older children and grownups.