He wanted to record thoughts and actions, and so his pictures tended to become symbols of ideas. The figure of an arrow might be made to represent, not a real object, but the idea of an "enemy." A "fight" could then be shown simply by drawing two arrows directed against each other. Many uncivilized tribes still employ picture writing of this sort. The American Indians developed it in most elaborate fashion. On rolls of birch bark or the skins of animals they wrote messages, hunting stories, and songs, and even preserved tribal annals extending over a century. SOUND WRITING; THE REBUS A new stage in the development of writing was reached when the picture represented, not an actual object or an idea, but a sound of the human voice. This difficult but all-important step appears to have been taken through the use of the rebus, that is, writing words by pictures of objects which stand for sounds. Such rebuses are found in prehistoric Egyptian writing; for example, the Egyptian words for "sun" and "goose" were so nearly alike that the royal title, "Son of the Sun," could be suggested by grouping the pictures of the sun and a goose. Rebus making is still a common game among children, but to primitive men it must have been a serious occupation. [Illustration: MEXICAN REBUS The Latin _Pater Noster,_ "Our Father," is written by a flag _(pan)_, a stone _(te)_, a prickly pear _(noch)_, and another stone _(te)_.] [Illustration: CHINESE PICTURE WRITING AND LATER CONVENTIONAL CHARACTERS] WORDS AND SYLLABLES In the simplest form of sound writing each separate picture or symbol stands for the sound of an entire word. This method was employed by the Chinese, who have never given it up. A more developed form of sound writing occurs when signs are used for the sounds, not of entire words, but of separate syllables. Since the number of different syllables which the voice can utter is limited, it now becomes possible to write all the words of a language with a few hundred signs. The Japanese, who borrowed some of the Chinese symbols, used them to denote syllables, instead of entire words. The Babylonians possessed, in their cuneiform [9] characters, signs for about five hundred syllables. The prehistoric inhabitants of Crete appear to have been acquainted with a somewhat similar system. [10] LETTERS The final step in the development of writing is taken when the separate sounds of the voice are analyzed and each is represented by a single sign or letter. With alphabets of a few score letters every word in a language may easily be written. [Illustration: CRETAN WRITING A large tablet with linear script found in the palace at Gnossus, Crete There are eight lines of writing, with a total of about twenty words Notice the upright lines, which appear to mark the termination of each group of signs.] EGYPTIAN HIEROGLYPHICS