On problems that concern his own comfort or safety the chimpanzee exercises the faculty of reason with a fair degree of precision. He is quick to interpret motives or to discern intents, and he is a rare judge of character. He is inquisitive, but not so imitative as monkeys are. He is more observant of the relations of cause and effect. In his actions he is controlled by more definite motives. He is docile and quickly learns anything that lies within the range of his own mental plane. The opinion has long prevailed that these apes subsist upon a vegetable diet. That is a mistake. In this respect their habits are much the same as those of man, except that the latter has learned to cook, but the former eats his food raw. Their natural tastes are greatly diversified, and they are not all equally fond of the same articles of food. Most of them are partial to the wild mango, which grows in abundance in certain localities in the forest. This is often available when other kinds of food are scarce. It thus becomes, as it were, a staple article of food. There are many kinds of nuts to be found in their domain, but the nut of the oil palm is a great favorite. They sometimes eat the kola nut, but they are not partial to it. Several kinds of small fruits and berries also form part of their diet. They eat the stalks of some plants, the tender buds of others, and the tendrils of certain vines. The names of these vines I do not know. Most of the fruits and plants that are relished by them are either acidulous or bitter in taste. They are not especially fond of sweet fruits. They prefer those having the flavors mentioned. They eat bananas, pineapples, or other sweet fruits, but rarely do so from choice. Most of them appear to prefer a lime to an orange, a plantain to a banana, a kola nut to a sweet mango. In captivity they acquire a taste for sweet foods of all kinds. In addition to these articles they devour birds, lizards, and small rodents. They rob birds of their eggs and their young. They make havoc of many kinds of large insects. Those that I have owned were fond of cooked meats and salt fish, either raw or cooked. CHAPTER XII The Speech of Chimpanzees--A New System of Phonetic Symbols--Some Common Words--Gestures The speech of chimpanzees (as of other simians) is limited to a few sounds, and these chiefly relate to their natural wants. The entire vocabulary of their language embraces perhaps not more than twenty-five or thirty words. Many of them are vague or ambiguous, but they express the concept of the ape with as much precision as it is defined to his mind, and quite distinctly enough for his purpose.