"I think, then," said Willy laughing, "that the whole carriage is like a house with three rooms in it, and that we are riding in one of the rooms; indeed it is so large that it looks almost as big as a little room." "Just so," replied his father. "Now, can you tell me how many people there are in the whole carriage?" "Yes," said Willy, carrying on the joke, "if there are three rooms and six persons in each, there must be eighteen in the whole house; for three times six makes eighteen in the multiplication table. But I should like to know how many people there are in the whole train, and that cannot be in the multiplication table, I think." "No," said his father; "there are, I believe, ten of these carriages, and eighteen times ten makes one hundred and eighty." "But," added he, "there are a great many other carriages of a different kind belonging to this train; they are called the second and third classes, and are cheaper, so that the common people can afford to go in them. The second class is not so well fitted up as this carriage (which is one of the first class), and is more exposed to the air; and the third class, which is the cheapest, is quite open." "Oh, then, I should like that best," said Willy; "for I like open carriages so much, you can see the horses;--oh no, not on the railroad," added he; "but then you see everything around you, without the trouble of looking out of the windows, and then the fresh air blows so nicely about you." "We will try them before we get to the end of our journey," said his father. "But," asked Willy, "how can one steam-engine be strong enough to draw all these carriages; for it is not alive? I know that men are strong, and horses are stronger, and elephants are stronger still, but they are all alive; I never knew anything strong that was not alive; did you, Mamma?" "Yes," replied she, laughing, "I once saw a little boy blown down by the wind; now the wind must have been strong to blow down the boy, and yet it is not alive. Then don't you remember when you bathed in the sea last summer, how strong the waves were? you often told me that if the bathing woman had not held you tightly, they would have thrown you down." "Oh yes," cried Willy, "and the waves are not alive; though they move about and froth so much, they are only sea water; but I am sure they are strong, very strong indeed. And is there anything else strong that is not alive?" "The steam from the steam-engine, which looks so light that you took it for smoke, is strong enough to draw this long heavy train. But observe, it is not the steam which you see flying about that moves the train, but that which is kept close inside the engine and cannot get out. Then the carriage wheels rolling on this smooth iron rail move more easily." "I thought," added he, "that iron rails always stood upright as they do in the railing before our house. I never saw an iron rail lying on the ground as these do, unless it was broken or thrown down."