The weather grew colder and the ice was pronounced safe. Skating began, and the chums from Tillbury soon showed the other girls how well they could skate together. Walter Mason declared he had just as soon skate with Nan Sherwood as with any boy he knew.
Nan and Bess went down to Mrs. Cupp's room one day to ask for the privilege of going to town to get their skates sharpened. It was late afternoon and growing dusky in the stairways. There was no light in Mrs. Cupp's room.
Before the girls reached the top of the flight leading to the basement they heard the matron scream. Then a sharp, shrill voice cried:
"I want my money! Give me my money! You and Miss Vane are trying to keep it from me. I want my money!"
"Go away! Go away!" the startled girls heard Mrs. Cupp murmur.
Bess had uttered a cry. Out of the matron's room scuttled a thin, black figure, which darted down the stairs.
"The boathouse ghost!" gasped Bess, clinging to Nan, in fright.
"Goodness!" returned Nan. "If it is, he's a long way off his beat, isn't he? Boathouse ghost, indeed!"
But when they went into the matron's room they found Mrs. Cupp lying back in her chair, in a pitiable state of fright.
Susan, her black face set in a very grim expression, came to wait upon Mrs. Cupp. "Go 'long, chillen," she commanded, "I'll 'tend to her."
"But she's been dreadfully frightened, Susan," cried Nan, sympathetically.
"She saw a ghost, Susan," whispered Bess, perhaps a little wickedly.
Susan rolled her eyes. "Go 'long, chile! Wot ghos'?"
"The boathouse ghost, I declare!" said Bess, with decision. "Wasn't it, Nan? All black--and small--and it squealed. Didn't it, Nan?"
"It was a boy," said her chum. "And he ran down cellar. Somebody ought to look into it."
"Into the cellar?" asked Bess, with a giggle, as Susan "shooed" them out of the matron's room and shut the door at their backs.
"Where do you suppose that boy went--if it was a boy?"
"I know," Nan said, hesitating at the top of the stairs.
"Goodness me! Is this another of your secrets, Nan Sherwood? You are the very meanest girl for a chum----"
"I never told you about this because so many other things came in between and made me forget," confessed Nan, quickly. "Come on! Let me show you."