Taylor's original application of Knock-Out was literally that. If you shoot an elephant in the head and do not get into the brain, the only tissue destroyed is bone. He claimed that a heavy enough blow would literally knock the animal out long enough for you to make another shot. I quote again:
"If you take a frontal head shot at an elephant with a .416 and miss the brain by a small amount, you will probably not knock him out. His hindquarters will give way and he will squat there like a huge hog for a few moments then, if you don't finish him off at once, he will heave to his feet again, slew around, and clear off. But if you had taken the shot with the .470, and missed the brain by the same amount, that elephant would have been knocked out entirely, unconscious, and would have remained down for anything up to about five minutes-yet the theoretical energies of the rifles are the same."
[.416 Ko = 57, .470 Ko = 70. He later says a .577 of Ko 126 will knock out an elephant for 25 minutes and a 600 at Ko 150 for 30 or more.]