"Do you know how to stop a train by pulling on the whistle cord?" he asked.
"Huh! I thought everybody knew that!" exclaimed Bunny. Then he laughed, as Wopsie did. It was a little joke on her, when Bunny answered her the way he did.
The automobile came to a stop in front of a large building. Bunny and Sue looked up at it.
"My! What a big house you live in, Aunt Lu!" said Bunny.
"Oh, this isn't all mine!" laughed Aunt Lu. "There are many others who live in here. This is what is called an apartment house. I have my dining room, kitchen, bath room and other rooms, and other families in this building have the same thing. You see there isn't room in New York to build separate houses, such as you have in Bellemere, so they make one big house, and divide it up on the inside, into a number of little houses, or apartments."
Bunny and Sue thought that very strange.
"But you haven't any yard to play in!" exclaimed Bunny, as he and his sister got out of the automobile, and found that the front door of Aunt Lu's apartment was right on the sidewalk.
"No, we don't have yards in the city, Bunny. But we have a roof to go up on and play."
"Playing on a roof!" cried Bunny. "I should think you'd fall off!"