something must be done about it.

"I can't stand it any longer," Betty confided to them one morning when
they stood on Mollie's porch discussing what course of action it would be
best to take. "I have a queer feeling that the poor professor is in
desperate need of friends, and I don't believe I'll be able to sleep
another night until I find out something definite about him."

"Won't he think we are sort of 'butting in'?" asked Grace, hesitating a
little. "He might think we came just out of curiosity."

"I don't think he would," said Mollie. "You know he invited us to come
back some time when we could stay long enough for him to tell us something
about those bugs and butterflies and things he sticks pins into--"

"That's the idea!" exclaimed Betty quickly. "We won't have to tell him we
know anything about his trouble. If he tells us--why, all right, but if he
doesn't, of course we won't try to force a confidence. Anyway," she
finished soberly, "we'll have the satisfaction of knowing we have done our
best for him whether it really helps him any or not."

"And we owe him a very great deal," spoke tip Amy softly. "He really saved
our lives, you know."

So it was settled, and while the other three girls ran home to put on
coats and hats and get ready for the drive, Mollie ran around to the
garage and brought her big car to the front of the house.

She waved good-bye to her mother, who was trying rather wildly to keep
Dodo and Paul from running under the wheels of the car and getting killed,