is sometimes a big slip between a wish and its fulfillment. Just
as Captain Jack was on the point of darting out into the street to hail
the policeman a street car whizzed by. With a flying leap the policeman
landed on the front platform and was whirled along the thoroughfare.

"Lesson number one about being too sure," grumbled disappointed young
Benson. "However, we'll soon come upon another policeman."

Two blocks more were covered, however, without sighting a bluecoat. Jack
even began to wonder how it would do to leap upon Millard, calling upon
passing citizens to aid him until a policeman arrived.

"But that would be a two-edged sword, that might cut too keenly on the
wrong side," reflected the submarine boy. "Millard would be sure to
claim that I was assaulting him. It would look like that, too, and
I'd probably get a thumping from the crowd, while Millard slipped away.
Then he would be warned that he was wanted, and he'd make himself mighty
scarce after that."

Still no policeman came into sight.

"Gracious!" muttered Jack Benson, suddenly. He had just glanced into a
store's show window, where a mirror was set at an angle. The submarine
boy, looking into that mirror, became aware that he could see people at
a considerable distance behind him down the street.

"I wonder if Millard has been taking sights, too, and has had a peep at
me, that way?" muttered the boy.

At the next corner the long-legged one, after a brief look down the side
street, turned into it.

"Now, that we're getting away from the main street there'll be far less
chance of finding a police officer," sighed Jack, at last wholly
discontented with luck.

Millard led without, apparently, ever thinking to glance back. He
turned a second corner, into another small street, and kept on.

"This is getting more exciting," muttered the young trailer. "Yet all
signs point to the fact that I've got to make the grab all by myself.
I wonder if I can down that chap and get the upper hand of him? I don't
mind a thumping, but I'd be sadly ashamed of myself to let the fellow
get away from me."

Millard was walking briskly, now. Next, he turned sharply to the left.

"Ah!" Then Jack Benson shot swiftly forward on tip-toe, trying to make
no noise as he ran.

For the long-legged one had, to all seeming, at the distance, wheeled
and gone through the wall of a brick building.

Just an instant later, however, this impossible feat was explained.