When the British naval officer comes ashore, he encounters what he considers very "bad form." The island is on fire and Ralph is dirty and sobbing. As the others emerge from the smoke, their clothes are in tatters. Ironically, the officer asks the boys if they have been playing war—"We saw your smoke. What have you been doing? Having a war or something?"—and Ralph nods seriously. Then the officer asks facetiously, "Nobody killed, I hope? Any dead bodies?" However, Ralph nods in such a way that the man realizes that Raph is telling the truth. He whistles his amazement softly to himself. Then, after a group of "painted boys" and one other boy with red hair beneath a tattered black cap who carries a pair of spectacles at his waist appear, the officer asks who is in charge. Ralph answers that he is. But, when Ralph is unable to account for how many boys there are, the officer is appalled at the lack of British order in this group of boys.

"I should have thought that a pack of boys—you're all British, aren't you?—would have been able to put up a better show than that—I mean—" (Ch. 12)

His comment suggests R.M. Ballantyne's adventure novel, The Coral Island, in which shipwrecked British boys on a Polynesian island are able to defeat savages with the civilizing effects of Christianity and British discipline and form. 

The officer's first reaction is to simply assume that the boys have just been larking about - it's all 'fun and games'. Even when he realises that the situation is more serious than that - when Ralph informs him that two boys have even been killed - he still responds with a kind of disbelief. He essentially fails to comprehend that boys, particularly British boys,  could ever act so savagely. His reference to R.M. Ballantyne's novel The Coral Island, which depicts boys having a carefree and wonderful time when abandoned on an island (in contrast to this novel) underlines this.