If the master were there he would say Rupert had sent him; if he wasn't, he would climb in at the window.

The sun was already sinking when he reached the clearing and found a cavalcade of armed men around the building.
Johnny's first conviction was that the master had killed Uncle Ben or Masters, and that the men, taking advantage of the absence of his--Johnny's--big brother, were about to summarily execute him.
Observing no struggle from within, his second belief was that the master had been suddenly elected Governor of California and was about to start with a state escort from the school-house, and that he, Johnny, was in time to see the procession.

But when the master appeared with McKinstry, followed by part of the crowd afoot, this quick-witted child of the frontier, from his secure outlook in the "brush," gathered enough from their fragmentary speech to guess the serious purport of their errand, and thrill with anticipation and slightly creepy excitement.
A duel! A thing hitherto witnessed only by grown-up men, afterwards swaggering with importance and strange technical bloodthirsty words, and now for the first time reserved for a BOY--and that boy him, Johnny!--to behold in all its fearful completeness! A duel! of which, he, Johnny, meanly abandoned by his brother, was now exalted perhaps to be the only survivor! He could scarcely credit his senses.

It was too much! To creep through the brush while the preliminaries were being settled, reach a certain silver fir on the appointed ground, and with the aid of his now lucky hatchet, climb unseen to its upper boughs, was an exciting and difficult task, but one eventually overcome by his short but energetic legs.

Here he could not only see all that occurred, but by a fortunate chance the large pine next to him had been selected as the limit of the ground.