“Nancy, where did those flies come from?”

“I don’t know, ma’am. There wasn’t one in the kitchen.” Nancy had been too excited to notice Pollyanna’s up-flung windows the afternoon before.

“I reckon maybe they’re my flies, Aunt Polly,” observed Pollyanna, amiably. “There were lots of them this morning having a beautiful time upstairs.”

Nancy left the room precipitately, though to do so she had to carry out the hot muffins she had just brought in.

“Yours!” gasped Miss Polly. “What do you mean? Where did they come from?”

“Why, Aunt Polly, they came from out of doors of course, through the windows. I saw some of them come in.”

“You saw them! You mean you raised those windows without any screens?”

“Why, yes. There weren’t any screens there, Aunt Polly.”

Nancy, at this moment, came in again with the muffins. Her face was grave, but very red.

“Nancy,” directed her mistress, sharply, “you may set the muffins down and go at once to Miss Pollyanna’s room and shut the windows. Shut the doors, also. Later, when your morning work is done, go through every room with the spatter. See that you make a thorough search.”

To her niece she said:

“Pollyanna, I have ordered screens for those windows. I knew, of course, that it was my duty to do that. But it seems to me that you have quite forgotten your duty.”

“My—duty?” Pollyanna’s eyes were wide with wonder.

“Certainly. I know it is warm, but I consider it your duty to keep your windows closed till those screens come. Flies, Pollyanna, are not only unclean and annoying, but very dangerous to health. After breakfast I will give you a little pamphlet on this matter to read.”

“To read? Oh, thank you, Aunt Polly. I love to read!”

Miss Polly drew in her breath audibly, then she shut her lips together hard. Pollyanna, seeing her stern face, frowned a little thoughtfully.

“Of course I’m sorry about the duty I forgot, Aunt Polly,” she apologized timidly. “I won’t raise the windows again.”

Her aunt made no reply. She did not speak, indeed, until the meal was over. Then she rose, went to the bookcase in the sitting room, took out a small paper booklet, and crossed the room to her niece’s side.

“This is the article I spoke of, Pollyanna. I desire you to go to your room at once and read it. I will be up in half an hour to look over your things.”

Pollyanna, her eyes on the illustration of a fly’s head, many times magnified, cried joyously:

“Oh, thank you, Aunt Polly!” The next moment she skipped merrily from the room, banging the door behind her.