Betty obeyed, but with no better success than the first time. Everything was as silent as before.
"Isn't there a bell, I wonder?" suggested Amy, wishing ardently that they were back on the road once more. "Perhaps your knock isn't loud enough for him to hear."
"We might tap on the window," suggested Grace. "If I use my ring on the window pane he surely ought to hear that."
She started to suit her action to the words when an exclamation from Betty made her pause. The latter had tried the door and found to her surprise that it gave to her touch.
"The door is unlocked," she said. "I don't believe the professor is in here at all and if he has gone into the woods to hunt his butterflies and beetles I am sure he wouldn't mind our going inside. What do you think?"
She was about to push the door open, but Grace detained her with a nervous hand on her arm.
"Oh, I don't think we had better go in, Betty!" she cried. "You know what we were speaking of in the car. Suppose we should find that he has--that he has--"
"That he has what?" asked Amy, her eyes wide. "For goodness' sake, what do you mean, Grace?"
Betty tried to stop her, but Grace hurried on heedlessly.
"He may have committed suicide," she cried, adding, in response to Mollie's and Amy's cry of horror: "You know he must have been desperate enough to do anything, poor old man, out here all alone."