Jim, yet he was
perfectly calm and contained as though he were the perfection of
wisdom. He folded his arms across his chest and regarded Tom serenely
as he sat on the opposite side of the deck on a coil of rope,
regarding his big brother skeptically. Eight minutes had passed, and
Tom, taking out his watch, recorded the fact with quiet triumph.

"Eight minutes and a quarter," he declared, "and no land in sight
yet."

"Eight and a half," he tolled, "nine!" Jim was apparently entirely
composed, but his mind had not yet reached a complete explanation. It
was, however, on the right track, but the time was short.

"Ten," cried Tom. "Speak up, Professor."

"It's your place first," he replied.

"Give it up."

"Now listen carefully," began Jim in a magisterial manner, "and if
there is anything you don't quite understand, raise your hand."

"Humph!" grunted Tom, "I guess that I can understand anything you can
tell me."

"Well, children, it's this way," continued Jim. "When you are upon
the land and you look at something in the distance your eyesight is
stretched from point to point by intervening objects, while on the
ocean your vision instead of being stretched out collapses as it were
because there is a monotonous level between your eye and the object.
Now I hope you will remember what I have just told you, children.
School is dismissed."

Jo seemed to be unduly impressed with the idea that he was a schoolboy
again, so he grabbed Tom's hat and made as if he was going to throw it
overboard. Tom made a grab for Jo and missed, then there was a great
chase around the main deck. Jo was very fleet of foot and gained on
his pursuer, until Tom saw that he must resort to stratagem; so no
sooner had Jo disappeared around the corner of the quarter deck than
Tom doubled back on his own trail, to the cook's galley, that had a
door opening on either side, so that one could step into either
passageway.

Tom leaped into the galley, and was quick to the other door, that he
opened a wee bit; he saw that Jo had just swerved into the passageway
and down he came full tilt toward where Tom lay in ambush, swinging
the latter's captured hat in his hand. Tom watched him eagerly, then
he sprang out from his hiding place directly in front of the flying
Jo, who was utterly surprised, but he was under such headway that he
could not stop.

Tom met him squarely and down they went in a heap, the lurch of the
ship sending Jo's head heavily ag