It is not at all rare to see a vast difference of manners, intelligence, and temperament among specimens that belong to one species. In these respects they vary as much in proportion to their mental scope as human beings do; but I have never seen, in any two apes of the same species, the two extremes so widely removed from one another.
While waiting at Gaboon for a steamer I had my own cage erected for the apes to live in, as it was large and gave them ample room for play and exercise. In one corner of it was suspended a small, cosy house for them to sleep in. It was furnished with a good supply of clean straw and some pieces of canvas for bedclothes. In the center of the cage was a swing, or trapeze, for them to use at their pleasure. Aaron found this a means of amusement, and often indulged in a series of gymnastics that might evoke the envy of a king of athletic sports.
Elisheba had no taste for such pastime, but her depravity could never resist the impulse to interrupt Aaron in his jolly exercise. She would climb up and contend for possession of the swing, until she would drive him away. Then she would perch herself on it and sit there for a time in stolid content; but she would neither swing nor play. Frequently during the day, when Aaron was lying quietly on the straw, she would go into the snug little house and raise a row with him by pulling the straw from under him, a handful at a time, and throwing it out of the box till there was none left in it. No matter what kind or quantity of food was given them, she always wanted the piece he had, and would fuss with him to get it; but having got it, she would sit holding it in her hand without eating it; for there were some things that he liked which she would not eat at all.
When we went out for a walk, no matter which way we started, Elisheba always contended to go some other way. If I yielded, she would again change her mind and start off in some other direction. If forced to submit, she would scream and struggle as if for life. I cannot forego the belief that these freaks were due to a base and perverse nature, and I could find no higher motive in her stubborn conduct.
Aaron was very fond of her and rarely ever opposed her inflexible will. He clung to her and let her lead the way. I have often felt vexed at him because he complied so readily with her wishes. The only case in which he took sides against her was in her conduct towards me.
When I first secured her she had the temper of a demon, and with the smallest pretext she would assault me and try to bite me or tear my clothes. In these attacks Aaron was always with me, and the loyal little champion would fly at her in the greatest fury. He would strike her over the head and back with his hands, and bite her and flog her till she desisted. If she returned the blow he would grasp her hand and bite it, or strike her in the face. He would continue to fight till she submitted. Then he would celebrate his victory by jumping up and down in a most grotesque fashion, stamping his feet, slapping his hands on the ground, and grinning like a mask. He seemed as conscious of what he had done and as proud of it as any human could have been; but no matter what she did to others, he was always on her side of the question. If any one else annoyed her, he would always resent it with violence.
About the premises there were natives all the time passing to and fro, and these two little captives were objects of special interest to them. They would stand by the cage hour after hour and watch them. The ruling impulse of nearly all natives appears to be cruelty, and they cannot resist the temptation to tease and torture anything that is not able to retaliate. They were so persistent in poking sticks at my chimpanzees that I had to keep a boy on watch all the time to prevent it; but the boy could not be trusted, so I had to watch him.
In the rear of the room that I occupied was a window through which, from time to time, I watched the boy and the natives, and when anything went wrong I would call out to the boy. Aaron soon observed this and found that he could get my attention himself by calling out when any one annoyed him, and he also knew that the boy was put there as a protector. Whenever any of the natives came about the cage he would call for me in his peculiar manner, which I well understood and promptly responded to. The boy also knew what the call meant and would rush to the rescue. If I were away from the house and the boy were aware of the fact, he was apt to be tardy in coming to the relief of the ape, and sometimes he did not come at all. In the latter event the two would crawl into their house and pull down the curtain so that they could not be seen. Here they would remain until the natives had left or some one came to their aid.
Neither of the apes ever resented anything the natives did to them, unless they could see me about; but whenever I came in sight they would make battle with their tormentors, and, if liberated from the big cage, they would chase the last one of them out of the yard. Aaron knew perfectly well that they were not allowed to molest him or his companion; and when he knew that he had my support he was ready to carry on the war to a finish. But it was really funny to see how meek and patient he was when left to defend himself alone against the native with a stick, and then to note the change in him when he knew that he was backed up by a friend upon whom he could rely.
Mr. Strohm, the trader, previously mentioned, with whom I found hospitality at this place, kept a cow in the lot where the cage was. She was a small black animal, the first cow that Aaron had ever seen. He never ceased to contemplate her with wonder and with fear. If she came near the cage when no one was about, he hurried into his box and from there peeped out in silence until she went away. The cow was equally amazed at the cage and its strange occupants, though she was less afraid than they, and frequently came near to inspect them. She would stand a few yards away with her head lifted high, her eyes arched and her ears thrown forward, waiting for them to come out of that mysterious box. But they would not venture out of their asylum while she remained. At last, tired of waiting, she would switch her tail, shake her head, and turn away.