The stranger was clad from head to foot in a suit of silver gray.  Upon his head he wore a peaked cap, upon his feet were the longest and most pointed of buskins; his doublet and hose were silver gray, and over his shoulders hung a mantle about which was a jagged border made after the most fantastic design, which shone and glittered like ice in sunlight.  About his hips was a narrow girdle from which hung a sheathed dagger whose hilt was richly studded with clear, white crystals that looked to Lionel like the purest of diamonds.

Lionel felt that when he spoke it would probably be after some old-century fashion which he could scarcely understand; but there he was mistaken, for when the stranger addressed him, it was in the most modern manner and with great kindliness.

“Well, my son,” he said cheerily, “tired out?  I saw you run.  You have a fine pair of heels.  They have good speed in them.”

“I wanted to catch up with someone,—­an old beggar-man who lost something in our area-way.  I wanted to return it to him,” explained Lionel, breathlessly.

The stranger gazed down at him more kindly than ever.  “So?  But one can’t expect to catch up with folks when one gets winded and has to stop every now and then for breath.  Better try my mode.”

“Please, sir, what is your mode?” inquired Lionel, with his politest manner.

“To begin with,” explained his companion, “I have to accomplish the most astonishing feats in the manner of speed.  Literally I have to travel so fast that I am in two places at once.  You will the better believe me when I tell you who I am,—­Jack Frost, at your service, sir.  Now, by what means do you think I manage it ?”

“I ’m sure I don’t know.  I should like immensely to find out,” Lionel returned.

“How do you get to places yourself?” inquired Jack Frost.  “Do you always run?”

“Oh, no, indeed.  I almost always ride on my bicycle.  Then I can go like anything, ’specially down coasts.  Upgrades are kind of hard sometimes, but not so very.  Oh, I can go quick enough when I have my bicycle.”

“Now then,” broke in Jack Frost, “you use a bicycle,—­that is, a machine having two wheels.  Now I use a something having but one wheel; consequently it goes twice as fast,—­oh! much more than twice as fast.”

“One wheel?” repeated Lionel, thoughtfully; “seems to me I never heard of that kind of an one.”

“Suppose you guess,” proposed Jack Frost.  “I ’ll put it in the form of a conundrum:  If a thing having two wheels is called a bicycle, what would a thing having but one be called?”

“Oh, that’s an old one.  I ’ve heard that before, and the answer is, a wheelbarrow, you know.”

Jack Frost shook his head, “I see I shall have to tell you,” he said.  “If a thing having two wheels is called a bicycle, a thing having but one would naturally be an icicle.  Of course you might have known I should use an icicle.”