Once, their powerful, wide-open jaws met one against the other in a hideous clash and something white and glistening flew out on to the grass. It was a broken tooth! The strength they were exerting must have been tremendous--sufficient to crush a man to jelly--and yet neither seemed able to gain any decisive advantage over the other. For nearly a couple of minutes we watched with horror and fascination this deadly combat between two of the cruellest and most vindictive brutes in the whole of the animal world. We could do nothing but stare breathlessly at the scene, and thank God that we were not actively involved as well. At last, however, one of us spoke. "We must stop this," whispered Stringer, hoarsely. "They'll kill each other." "What can we do--except shoot?" "There's . . . _this_!" he answered quietly. "If we can get near enough." He held up the nozzle of the gas projector. "By jove!" I said. "Of course!" I gave the prearranged sign to the two scared negroes crouching in the cage and they turned on the cocks of the cylinders. As the gas began sizzling out of the flexible tubes, we fixed over our nostrils the breathing apparatus connected with the filters which we carried on our backs. Then we advanced stealthily towards the gyrating mass of animal fury and played on it. The miraculous happened. Gradually, the monsters relinquished their stranglehold. It was as if sudden exhaustion had seized them. They sat down on their haunches, like two worn-out old men, panting for breath, dazed and clearly very surprised. One of them made a whimpering noise, opened its mouth in a vain endeavor to escape the suffocating effects of the gas, passed its arm wearily across its face as if to wipe something away--and suddenly collapsed. The other attempted to escape. But its legs and arms were too weak to propel its great body and a moment or so later it, too, lay down with a deep grunt of contentment. I shouted to the negroes--shouted at the top of my voice in modern English: "Hustle, there!" They understood. Without a second's delay they came running out to us with all the paraphernalia of bondage--ropes, chains, handcuffs, and sacks. I gave Stringer my gas projector, asked him to keep the two brutes quiet while I fetched the ether, and told the negroes to hold their breath until they had dropped their burden and retreated again. For the next five minutes we were four of the busiest people on earth. We substituted ether for gas, got the gorillas into a nice pliable condition of utter unconsciousness, handcuffed their hands behind their backs, tied up their legs in sacks, wound their arms and bodies round and round with ropes and chains, and then withdrew to our cage, where we took a cool and refreshing draught of lime-juice and water.