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CHAPTER VI
THE SPEECH OF CHIMPANZEES

The speech of chimpanzees is limited to a few sounds, and these are confined chiefly to their natural wants. The entire vocabulary of their language embraces perhaps not more than twenty words, and 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.

In my researches I have learned about ten words of his speech, so that I can understand them, and make myself understood by them. Most of these sounds are within the compass of the human voice, in tone, pitch, and modulation; but two of them are much greater in volume than it is possible for the human lungs to reach, and one of them rises to a pitch more than an octave higher than any human voice. These two sounds are audible at a great distance, but they do not fall within the true limits of speech.

The vocal organs of this ape resemble those of man as closely as any other character has been shown to resemble. They differ slightly in one detail that is worthy of notice. Just above the opening called the glottis, which is between the vocal cords, are two small sacs or ventricles. These, in the ape, are larger and more flexible than in man. In the act of speaking they are inflated by the air passing out of the lungs through the long tube called the larynx. The function of these organs is to control and modify the sound by increasing or decreasing the pressure of the air that is jetted through this tube. They serve, at the same time, as a reservoir and a gauge.

In the louder sounds produced by the chimpanzee these ventricles distend until the membrane of which they are composed is held at a high tension. This greatly intensifies the voice, and increases its volume. It is partly due to these little sacs that the ape is able to make such a loud and piercing scream. But the pitch and volume of his voice cannot be due to this cause alone, for the gorilla, in which these ventricles are much smaller, can make a vastly louder sound, unless we are mistaken about the one ascribed to him.

Although the sounds made by the chimpanzee can be imitated by the human voice, they cannot be expressed or represented by any system of phonetic symbols in use among men. All alphabets have been deduced from pictographs, and the symbol that represents any given sound has no reference to the organs that produced it. The few rigid lines that have survived to form the alphabets are conventional, and within themselves meaningless, but they have been so long used to represent these sounds of speech that it would be difficult to supplant them with others, even if such were desired.

As no literal formula can be made to represent the phonetic elements of the speech of chimpanzees, I have taken a new step in the art of writing by framing a system of my own, which is rational in plan and simple in device.

The organs of speech always act in harmony, and a certain movement of the lips is always attended by a certain movement of the internal organs of speech. This is true of the ape as well as of man, and in order to utter the same sounds each would employ the same organs, and use them in the same way.

By this means, deaf mutes are able to distinguish the sounds of speech and reproduce them, although they do not hear them. By close study and long practice they learn to distinguish the most delicate shades of sound.

In this plain fact lies the clue to the method I have used. It is, as yet, only in the infant state, but it is possible to be made, with a very few symbols, to represent the whole range of vocal sounds made by man or other animals.

The chief symbols I employ are the parentheses used in common print. The two curved lines placed with the convex sides opposite, thus, (), represent the open glottis, in which position the voice will utter the deep sound of "O." The glottis about half closed utters the sound of "U," as in the German, and to represent this sound a period is inserted between the two curved lines, thus, (.). When the aperture is contracted still more it produces the sound of "A" broad, and to represent this a colon is placed between the lines, thus, (:). When the aperture is restricted to a still smaller compass the sound of "U" short is uttered, and to represent this an apostrophe is placed between the lines, thus, ('). When the vocal cords are brought to a greater tension, and the aperture is almost closed, it utters the short sound of "E." To represent this sound a hyphen is inserted between the lines, thus, (-). These are the main vowel sounds of all animals, although in man they are sometimes modified, and to them is added the sound of "E" long, while in the ape the long sounds of "O" and "E" are rarely, if ever, heard.

From this vowel basis all other sounds may be deduced, and by the use of diacritics to indicate the movement of the organs of speech, the consonant elements may be easily expressed.

A single parenthesis, with the concave side to the left, will represent the initial sound of "W," which seldom, but sometimes, occurs in the sounds of animals. When used, it is placed on the left side of the leading symbol, thus,)(), and this symbol, as it stands, should be pronounced nearly like "U-O," but with the first letter suppressed, and almost inaudible. Turning the concave side to the right, and placing it on the right side of the symbol, it represents the vanishing sound of "W," thus, ()(. This symbol reads "O-U," with the "O" long, and the "W" depressed into the short sound of "U." The apostrophe placed before or after the symbol will represent "F" or "V." The grave accent, thus, (`), represents the breathing sound of "H," whether placed before or after the symbol, and the acute accent, thus, (´), will represent the aspirate sound of that letter in the same way.

When the symbol is written with a numeral exponent, it indicates the degree of loudness. If there is no figure, the sound is such as would be made by the human voice in ordinary speech. The letter "X" will indicate a repetition of the sound, and the numeral placed after it will show the number of times repeated, instead of the degree of loudness. For example, we will write the sound (.), which is equivalent to long "U," made in a normal tone, the same symbol written thus (.)2 indicates the sound, made with greater energy, and about twice as loud. To write it thus, (.)X2, indicates that the sound was repeated, and so on.

One peculiar sound made by these animals, which is described in connection with the gorilla, appears to be the result of inhalation, but I know of no other animal that makes a sound in this manner.

As an example of the use of this method, we will write the French word "feu," which Moses mastered, thus, '('), which is equivalent to "vû" with the "U" sounded short, the other word "wie," in German, thus,)('), which is pronounced almost like "wû," giving "u" the short sound again.

I shall not lead the reader through the long and painful task by giving the entire system as far as I have gone, but what has been given will convey an idea of a system, by means of which it will be possible to represent the sounds of all animals, so that the student of phonetics will recognise at once the character of the sound, even if he cannot reproduce it by natural means.

It would be tedious and of no avail to the casual reader to reduce to writing here the sounds made by the chimpanzee; but it may be of interest to mention and describe the character and use of some of them.

Perhaps the most frequent sound made by all animals, appears to be that referring to food, and therefore it may claim the first place in our attention. This word in the language of the chimpanzee begins with the short sound of the vowel "u" which blends into a strong breathing sound of "h," the lips are compressed at the sides, and the aperture of the mouth is nearly round. It is not difficult to imitate, and the ape readily understands it even when poorly made.

Another sound of frequent use among them is that used for calling. The vowel element is nearly the same, though slightly sharpened, and merges into a distinct vanishing "w." The food sound is often repeated two or three times in succession, but the call is rarely ever repeated, except at long intervals.

One sound is particularly soft and musical, the vowel element is that of long "u" as in the German. This blends into a "w," followed by the slightest suggestion of the short sound of "a." It appears to express affection or love. This sound is also the first of the series of sounds attributed to the gorilla.

The most complex sound made by them is the one elsewhere described as meaning "good." They often use it in a sense very much the same as mankind uses the word "thanks," but it is not probable that they use it as a polite term, yet the same idea is present.

One of the words of warning or alarm contains a vowel element closely resembling the short sound of "e." It terminates with the breathing sound of "h." It is used to announce the approach of anything that he is familiar with, and not afraid of. If the sound is intended to warn against the approach of an enemy, or something strange, the same vowel element is used, but terminates with the aspirate sound of "h" pronounced with energy and distinctness. The two words are the same in vowel quality, but they differ in the time required to utter them, and the final breathing and aspirate effects. There is also a difference in the manner of the speaker in the act of delivering the word, which plainly indicates that he knows the use and value of the sounds. At the approach of danger the latter is often given almost in a whisper, and at long intervals apart, but increases in loudness as the danger approaches; the other is usually spoken distinctly and repeated frequently. It is worthy of note that the native tribes often use the same word in the same manner and for the same purpose.

There are other sounds which are easily identified but difficult to describe, such as that used to signify "cold" or "discomfort"; another for "drink"; another referring to "illness," and still another which I have good reason to believe means "dead" or "death." There are perhaps a dozen more that I can distinguish, but have not yet been able to determine their meaning. I have an opinion as to some of them which I have not yet verified.

The chimpanzee makes use of a few signs which seem to be fixed factors of expression. He makes a negative sign by moving the head from side to side, but the gesture is not frequent or pronounced. Another negative sign, which is more common, is a motion of the hand from the body towards the person or thing addressed. This sign is sometimes made with great emphasis, and there can be no question as to what it means. The manner of making the sign is not uniform. Sometimes it is done by an urgent motion of the hand. Bringing it from his opposite side, with the back forward, it is waved towards any one approaching, if the ape object to the approach. The same sign is often made as a refusal of anything offered him. Another way of making this sign is with the arm extended forward, the hand hanging down, and the back towards the person approaching or the thing refused. In addition to these negative signs there is one which may be regarded as affirmative. It is made simply by extending one arm towards the person or thing desired. It sometimes serves the purpose of beckoning; but in this act there is no motion of the hand. These signs are similar in character to those used by men, and appear to be innate.

It must not be inferred from this small list of words and signs that there is nothing left to learn. So far we have only taken the first step as it were in the study of the speech of apes. As we grow more familiar with their sounds, it becomes less difficult to understand them. I have not been disappointed in what I hoped to learn from these animals. The total number of words in the speech of all simians that I have learned up to this time is about one hundred. I have given no attention of late to the small monkeys, but I shall resume the task at some future day, as it forms a part of the work I have assumed, but all of that is described in a work already published.

In conclusion, I will say that the sounds uttered by these apes have all the characteristics of true speech. The speaker is conscious of the meaning of the sound used, and uses it with the definite purpose of conveying an idea to the one addressed; the sound is always addressed to some definite one, and the speaker usually looks at the one addressed; he regulates the pitch and volume of the voice to suit the condition under which it is used; he knows the value of sound as a medium of thought. These and many other facts show that they are truly speech.

If these apes were placed under domestication, and kept there as long as the dog has been, he would be as far superior to the dog in sagacity as he is by nature above the wild progenitors of the canine race.

CHAPTER VII
THE CAPTURE AND CHARACTER OF MOSES

During my sojourn in the forest, I had a fine, young chimpanzee, which was of ordinary intelligence, and of more than ordinary interest, because of his history.

I gave him the name Moses, not in derision of the historic Israelite of that name, but because of the circumstances of his capture and life.

He was found all alone in a wild papyrus swamp of the Ogowe River. No one knew who his parents were, or how he ever came to be left in that dismal place. The low bush in which he was crouched when discovered was surrounded by water, and the poor little waif was cut off from the adjacent dry land.

As the native who captured him approached, the timid little ape tried to climb up among the vines above him, and escape, but the agile hunter seized him before he could do so. At first the chimpanzee screamed, and struggled to get away, because he had perhaps never before seen a man, but when he found that he was not going to be hurt, he put his frail arms around his captor, and clung to him as a friend. Indeed, he seemed glad to be rescued from such a dreary place, even by such a strange creature as a man.

For a moment the man feared that the cries of his young prisoner might call its mother to the rescue, and possibly a band of others; but if she heard them, she did not respond, so he tied the baby captive with a thong of bark, put him into his canoe, and brought him away to the village, where he supplied him with food, and made him quite cosy. The next day he was sold to a trader. About this time I passed up the river on my way to the jungle in search of the gorilla and other apes. Stopping at the station of the trader, I bought him, and took him along with me. We soon became the best of friends and constant companions.

It was supposed that the mother chimpanzee left her babe in the tree while she went off in search of food, and wandered so far away that she lost her bearings and could not again find him. He appeared to have been for a long time without food, and may have been crouching there in the forks of that tree for a day or two; but such was only inferred from his hunger, as there was no way to determine how long he had remained, or even how he got there.

I designed to bring Moses up in the way that good chimpanzees ought to be brought up, so I began to teach him good manners in the hope that some day he would be a shining light to his race, and aid me in my work among them. To that end I took great care of him, and devoted much time to the study of his natural manners, and to improving them as much as his nature would allow.

I built him a neat little house within a few feet of my cage. It was enclosed with a thin cloth, and had a curtain hung at the door, to keep out mosquitoes and other insects. It was supplied with plenty of soft, clean leaves, and some canvas bed-clothing. It was covered over with a bamboo roof, and suspended a few feet from the ground, so as to keep out the ants.

Moses soon learned to adjust the curtain, and go to bed without my aid. He would lie in bed in the morning until he heard me or the boy stirring about the cage, when he would poke his little black head out, and begin to jabber for his breakfast. Then he would climb out, and come to the cage to see what was going on.

He was not confined at all, but quite at liberty to go about in the forest, climb the trees and bushes, and have a good time of it. He was jealous of the boy, and the boy was jealous of him, especially when it came to a question of eating. Neither of them seemed to want the other to eat anything that they mutually liked, and I had to act as umpire in many of their disputes on that grave subject, which seemed to be the central thought of both of them.

I frequently allowed Moses to dine with me, and I never knew him to refuse, or to be late in coming on such occasions, but his table etiquette was not of the best order. I gave him a tin plate and a wooden spoon, but he did not like to use the latter, and seemed to think that it was pure affectation for any one to eat with such an awkward thing. He always held it in one hand, while he ate with the other, or drank his soup out of the plate.

It was such a task to get washing done in that part of the world, that I resorted to all means of economy in that matter, and for a tablecloth I used a leaf of newspaper, when I had it. To tear that paper afforded Moses an amount of pleasure that nothing else would, and in this act his conduct was more like that of a naughty child than in anything he did.

When he would first take his place at the table, he behaved in a nice and becoming manner; but having eaten till he was quite satisfied, he usually became rude and saucy. He would slily put his foot up over the edge of the table, and catch hold of the corner of the paper, meanwhile watching me closely, to see if I was going to scold him. If I remained quiet he would tear it just a little and wait to see the result. If no notice was taken of that, he would tear it a little more, but keep watching my face to see when I observed it. If I raised my finger to him, he quickly let go, drew his foot down, and began to eat. If nothing more was done to stop him, the instant my finger and eyes were dropped, that dexterous foot was back on the table and the mischief resumed with more audacity than before.

When he carried his fun too far, I made him get down from the table and sit on the floor. This humiliation he did not like at best, but when the boy would grin at him for it, he would resent it with as much temper as if he had been poked with a stick. He certainly was sensitive on this point, and evinced an undoubted dislike to being laughed at.

Another habit that Moses had was putting his fingers in the dish to help himself. He had to be watched all the time to prevent this, and seemed unable to grasp any reason why he should not be allowed to do so. He always appeared to think my spoon, knife and fork were better than his own spoon. On one occasion he persisted in begging for my fork until I gave it to him. He dipped it into his soup, held it up, and looked at it as if disappointed. He again stuck it into his soup, and then examined it, as if to see how I lifted my food with it. He did not seem to notice that I used it in lifting meat instead of soup. After repeating this three or four times, he licked the fork, smelt it, and then deliberately threw it on the floor, as if to say, "That's a failure." He leaned over and drank his soup from the plate.

The only thing that he cared much to play with was a tin can that I kept some nails in. For this he had a kind of mania, and never tired of trying to remove the lid. When given the hammer and a nail, he knew what they were for, and would set to work to drive the nail into the floor of the cage or the table; but he hurt his fingers a few times, and after that he stood the nail on its flat head, removed his fingers and struck it with the hammer, but, of course, never succeeded in driving it into anything.

A bunch of sugar-cane was kept for Moses to eat when he wanted it, and to aid him in tearing the hard shell away from it, I kept a club to bruise it. Sometimes he would go and select a stalk of the cane, carry it to the block, take the club in both hands, and try to mash the cane himself; but as the jar of the stroke often hurt his hands, he learned to avoid this, by letting go as the club descended. He never succeeded in crushing the cane, but would continue his efforts until some one came to his aid. At other times he would drag a stalk of the cane to the cage, poke it through the wires, then bring the club, and poke it through, to get me to mash it for him.

From time to time I received newspapers sent me from home. Moses could not understand what induced me to sit holding that thing before me, but he wished to try it, and see. He would take a leaf of it, and hold it up before him with both hands, just as he saw me do; but instead of looking at the paper, he kept his eyes, most of the time, on me. When I would turn mine over, he did the same thing, but half the time had it upside down. He did not appear to care for the pictures, or notice them, except a few times he tried to pick them off the paper; and one large cut of a dog's head, when held at a short distance from him, he appeared to regard with a little interest, as if he recognised it as that of an animal of some kind, but I cannot say just what his ideas concerning it really were.

Chimpanzees are not usually so playful or funny as monkeys, but they have a certain degree of mirth in their nature, and at times display a marked sense of humour.

One thing that Moses liked was to play peek-a-boo with me or the boy. He did not try to conceal his body from view, but would hide his eyes, and then peep. A favourite time for this was in the early part of the afternoon. He would often go and put his head behind a large tin box in the cage, while his whole body was visible. In this attitude he would utter a series of peculiar sounds, then draw his head out, and look at me, to see if I was watching him. If not, he would repeat the act a few times, and then hunt something else to amuse himself with. But if he could gain attention, the romp began, and he found great pleasure in this simple pastime. He would roll over, kick up his heels, and grin, with evident delight.

I spent much time in entertaining him in this way, and felt amply repaid for it in the gratification it afforded him. I could not resist his overtures to play, as he was my companion and my friend, and, living in that solitary gloom, it was a mutual pleasure.

Another occasion on which he used to peep at me was when he lay down to take his midday nap. For this I had made him a little hammock, which was suspended by wires, so that it could be removed when not in use. I always hung this by my side in the cage, so I could swing him to sleep like a child. He liked this, and I liked to indulge him. When he was laid in it, he was usually covered up with a small piece of canvas, and in spreading it over him, I frequently laid the edge of it over his eyes, but he seemed to suspect me of having some motive in doing so. Often he would reach his fingers up, catch the edge of the cloth, and gently draw it down, so he could see what I was doing. If he saw that he was detected, he would quickly release it, and cuddle down, as if it had been done by accident; but the little rogue knew, just as well as I did, what it meant to peep.

I also made him another hammock, and hung it out a few yards from the cage, so he could get into it without bothering me; but he never cared for it, until I brought a young gorilla to live with us in our jungle home, and as Moses never used it, I assigned it to the new member of the household. Whenever the gorilla got into it there was a small row about it. Moses would never allow him to occupy it in peace. He seemed to know that it was his own by right, and the gorilla was regarded as an intruder. He would push and shove the gorilla, grunt and whine and quarrel, until he got him out of it; but after doing so he would leave it, and climb up into a bush, or go away to hunt something to eat. He only wanted to dispossess the intruder, for whom he nursed an inordinate jealousy. He never went near the gorilla's little house, which was on the opposite side of the cage from his own; even after the gorilla died, he kept aloof from it.

As a rule, I always took Moses with me in my rambles into the forest, and I found him to be quite useful in one way. His eyes were like the lens of a camera – nothing escaped them; and when he discovered anything in the jungle, he always made it known by a peculiar sound. He could not point it out with his finger, but by watching his eyes the object could often be located.

Frequently during these tours the ape rode on my shoulders, and at other times the boy carried him, but occasionally he was put down on the ground to walk. If we travelled at a very slow pace, and allowed him to stroll along at leisure, he was content to do so, but if hurried beyond a certain gait he always made a display of his temper. He would turn on the boy and attack him, if possible; but if the boy escaped, the angry little ape would throw himself down on the ground, scream, kick, and beat the earth with his own head and hands in the most violent and persistent manner. He sometimes did the same way when not allowed to have what he wanted. His conduct was exactly like that of a spoiled, ugly child.

He had a certain amount of ingenuity, and often evinced a degree of reason which was rather unexpected. It was not a rare thing for him to solve some problem that involved a study of cause and effect, but always in a limited degree. I would not be understood to mean that he could work out any abstract problem, such as belongs to the realm of mathematics, but simple, concrete problems, where the object was present.

On one occasion, while walking through the forest we came to a small stream of water. The boy and myself stepped across it, leaving Moses to get over it without help. He disliked getting his feet wet, and paused to be lifted across. We walked a few steps away, and waited. He looked up and down the branch to see if there was any way to avoid it. He walked back and forth a few yards, but found no way to cross it. He sat down on the bank, and declined to wade it. After a few moments he waddled along the bank, about ten or twelve feet, to a clump of tall slender bushes growing by the edge of the stream. Here he halted, whined, and looked up into them thoughtfully. At length he began to climb one of them that leaned over the water. As he climbed up, the stalk bent with his weight, and in an instant he was swung safely across the little brook. He let go the plant, and came hobbling along to me with a look of triumph on his face that plainly indicated that he was fully conscious of having performed a very clever feat.

One dark, rainy night I felt something pulling at my blanket and mosquito bar. I could not for a moment imagine what it was, but knew that it was something on the outside of my cage. I lay for a few seconds, and felt another strong pull at them. In an instant some cold, damp, rough thing touched my face, and I found it was his hand poked through the meshes and groping about for something. I spoke to him, and he replied with a series of plaintive sounds which assured me that something must be wrong.

I arose, and lighted a candle. His little brown face was pressed up against the wires, and wore a sad, weary look. He could not tell me in words what troubled him, but every sign, look, and gesture bespoke trouble. Taking the candle in one hand, and my revolver in the other, I stepped out of the cage and went to his domicile, where I discovered that a colony of ants had invaded his quarters.

These ants are a great pest when they attack anything, and when they make a raid on a house the only thing to be done is to leave it until they have devoured everything about it that they can eat. When they leave a house there is not a roach, rat, bug, or insect left in it.

As the house of Moses was so small, it was not difficult to dispossess them by saturating it with kerosene, which was quickly done, and the little occupant allowed to return and go to bed. He watched the procedure with evident interest, and seemed perfectly aware that I could rid him of his savage assailants. In a wild state he would doubtless have abandoned his claim, and fled to some other place without an attempt to drive them away, but in this instance he had acquired the idea of the rights of possession.

Moses was especially fond of corned beef and sardines, and would recognise a can of either as far away as he could see it. He also knew the instrument used in opening them, but he did not appear to appreciate the fact that when the contents had once been taken out it was useless to open the can again, so he often brought the empty cans that had been thrown into the bush, would get the can-opener down, and want me to use it for him. I never saw him try to open it himself, except with his fingers. Sometimes, when about to prepare my own meals, I would open the case in which I kept stored a supply of canned meats, and allow Moses to select one for the purpose. He never failed to pull out one of the cans of beef, bearing the red and blue label. If I put it back he would select the same kind, and could not be deceived in his choice. It was not accidental, because he would hunt for one until he found it.

I don't know what he thought when it was not served for dinner, as I often exchanged it for another kind without consulting him.

I kept my supply of water in a large jug, which was placed in the shade of the bushes near the cage. I also kept a small pan for Moses to drink out of. He would sometimes ask for water, by using his own word for it. He would place his pan by the side of the jug and repeat the sound a few times. If he was not attended to he proceeded to help himself. He could take the cork out of the jug quite as well as I could. He would then put his eye to the mouth of it, and look down into the vessel to see if there was any water. Of course the shadow of his head would darken the interior of the jug so that he could not see anything. Then removing his eye from the mouth of it, he would poke his hand in it, but I reproved him for this until I broke him of the habit. After a careful examination of the jug he would try to pour the water out. He knew how it ought to be done, but was not able to handle the vessel himself. He always placed the pan on the lower side of the jug; then leaned the jug towards it and let go. He would rarely ever get the water into the pan, but always turned the jug with the neck down grade. As a hydraulic engineer he was not a great success, but he certainly knew the first principles of the science.