Mr. Horton laughed.
"The subway isn't what you ride on," he tried to explain. "It's what you ride in. The trains go through the subway, Sunny."
Mrs. Horton came out with her postage stamps just then, and the three walked till they came to one of the funny little houses Sunny Boy had seen at many street corners. Mr. Horton led the way straight down the steps.
"Why, we're going down cellar!" exclaimed the astonished little boy, who followed him. "Daddy, do the trains run in the cellar?"
It was clear that they did, for even before they reached the last step the rumble and roar of a coming train was heard. It was light and bright in the subway station, and Sunny Boy thought that it did not seem like a cellar at all.
He stood as close to the edge of the platform as his father would let him and peered up the track. It was dark, like a tunnel, and colored lights winked at him from the walls.
"Will the next be our train?" he asked.
"We can take any that comes," answered Daddy. "This is an express station. See the red light coming—that is a train."
A tiny red glow far in the distance grew larger and larger, and the roar and rumble of the train was heard. A long train of cars, brilliantly lighted, swept past them, such a long train that Sunny Boy thought at first that it was not going to stop. But it did.
"Where's the engine?" he asked disappointedly, as he and Mother and Daddy stepped on through a center door.