midday
Dave 's face , a trifle too somber at all times , took on a grimmer aspect now ; he felt a slow fury kindling in his breast . Years of experience had taught him to be always alert even during his moments of deepest preoccupation , and so , from force of habit , when he came to the pump-house road he carefully scanned it . In the dust were fresh hoof-prints leading toward the river . Now he knew this road to be seldom used , and therefore he wondered who could be riding it at a gallop in this blistering midday heat . A few rods farther on and his quick eye detected something else -- something that brought him from his saddle . Out of the rut he picked a cigarette butt , the fire of which was cold but the paper of which was still wet from the smoker 's lips . He examined it carefully ; then he remounted and rode on , pondering its significance .