Nan lay upon the couch in her room, resting after her exertions, when Grace, who had been telephoning to Walter, came in bursting with news.
"What do you think I heard downstairs!" she cried before she was fairly in the room. "Doctor Beulah thinks that it wasn't an accident at all, but that the whole thing was caused by some one tampering with the boiler."
The girls all spoke at once.
"Oh, that couldn't be!"
"Who'd have any object in doing a thing that might have cost lives?"
"Isn't it awful!"
"Anyway," Grace went on as soon as they gave her a chance to speak, "they say that a heavy cord had been tied to the valve to keep it down and the broken ends of the cord were found hanging from it."
The girls were stupefied with astonishment.
Suddenly Laura started up and walked excitedly about the room.
"There's this much about it!" she exclaimed. "If some one did do it purposely, Doctor Beulah will soon find out when it was done, and why it was done—and who did it, too," she added significantly.