"Is anything the matter?" asked Mark.

"I don't know," answered Jack. "It says: 'Come home at once.'
I wonder what's wrong?"

"I hope nothing serious," said Professor Lenton.

"You may both prepare to leave this afternoon. I am sorry. Let
me hear from you when you reach Professor Henderson. I trust
nothing has happened to him. He is too great a scientist for us
to lose."




CHAPTER III

WASHINGTON MEETS THE BOYS


All thoughts of experiments were driven from the minds of Jack
and Mark by the telegram. They imagined that something had
happened to their old friend, and it worried them. If he was
dangerously hurt, as might be, for he was constantly experimenting
in a small way, it would mean that a great change must take place
in their lives.

"What do you suppose can have happened?" asked Mark, as he and
Jack went to their rooms to get ready to leave the college.