Arrived at the drill ground, the cadets dismounted, standing by their horses in a little group until Captain Albutt should ride out of one of the cavalry stables and take command.

Haynes, with a rapid throbbing of his pulses, bent forward and down, pretending to examine his horse’s nigh forefoot.

As he did so, with an expertness gained of practice, Haynes slipped the head of the black pin in under the front of the sole of his right boot.  Then he straightened up again, chatting with Pierson.

“I say, Haynes,” drawled Anstey, a few moments later, glancing at the turnback’s right foot, “that’s a dangerous-looking thing you have in your boot.”

“What’s that?” demanded Haynes, losing color somewhat, yet pretending to be surprised.

“That long pin, sticking out of the front of your right boot,” continued Anstey, pointing.

Haynes glanced down, saw the thing, and pretended to be greatly astonished.

“How did I get that thing in my shoe?” he cried.

Then, with an appearance of indolent indifference that was rather overdone, the turnback stooped low enough to extract the pin.  But his fingers trembled in the act, and half a dozen cadets noted the fact.

“That’s a reckless bit of business, Haynes,” continued Anstey in a voice that did not appear to be accusing.

“Reckless?” gasped Greg Holmes.  “It’s criminal!”

“What do you mean?” demanded Haynes, straightening himself and glaring coldly into Holmes’s eyes.

But Greg was one of the last fellows in the world to permit himself to be “frozen.”

“I mean what I say, Haynes,” he retorted plumply.  “With that thing in the toe of your boot something would be likely to happen when some other horse’s flank bumped you on the right.  And, by George, it’s Prescott who rides at your right in platoon or column of fours!”

Greg shot a look full of keen suspicion at the turnback.

“And it was Prescott who rode on your right the day he was thrown from Satan!” flashed Greg, his face going white from the depth of his sudden feeling.  “Haynes, did you have that pin in the toe of your boot the day that Prescott was thrown in the riding hall?”

“You-----” Haynes began, at white heat, clenching his free fist.

“Answer me!” broke in Greg insistently.

“I did not!”

“I don’t believe you!” shot back Cadet Holmes

“Confound you, sir, do you mean to call me a liar?” hissed the turnback.

“Yes!” replied Greg promptly.

Haynes dropped his bridle, stepping toward Greg Holmes, who, however, neither flinched nor looked worried.

“Hold my lines, Dobbs,” urged Pierson, passing his bridle over to a fellow classman.

Then Pierson sprang in front of Greg, facing his roommate.

“Softly, Haynes!” cried Pierson warningly.

“What is this to you?” demanded the turnback hotly.