Other accounts tell that the descendants of the Quiches still use the quipu, perhaps as modified by themselves, for numeration. They pierce beans and hang them by different colored strings, each of which represents one of the column places used in decimal arithmetic. A green string signifies 1,000; a red one, 100; a yellow, 10, and a white refers to the 9 smaller digits. Thus if 7 beans are on a green, 2 on a red, 8 on a yellow, and 6 on a white string, and the whole tied together, the bundle expresses the number 7,286. Before the time of their acquaintance with the quipus, the Peruvians used in the same way pebbles or maize-beans of various colors. The same practice was known in Europe in the prehistoric period. The habit of many persons in civilized countries to tie a knot in the handkerchief to recall an idea or fact to mind is a familiar example to show how naturally the action would suggest itself for the purpose, and perhaps indicates the inheritance of the practice. [Illustration: BUREAU OF ETHNOLOGY TENTH ANNUAL REPORT PL. XVI PERUVIAN QUIPU AND BIRCH BARK DRAWING.] Dr. Andree (_b_) gives an illustration of a quipu (here reproduced as part of Pl. XVI), which he represents as taken from Perez, and states that the drawing was made soon after the exhuming of the object from an ancient Peruvian grave. Capt. Bourke (_a_) gives descriptions and illustrations of varieties of the izze-kloth or medicine cord of the Apache. A condensed extract of his remarks is as follows: These cords, in their perfection, are decorated with beads and shells strung along at intervals, with pieces of the sacred green chalchihuitl, which has had such a mysterious ascendancy over the minds of the American Indians--Aztec, Peruvian, Quiche, as well as the more savage tribes like the Apache and Navajo; with petrified wood, rock crystal, eagle down, claws of the hawk or eaglet, claws of the bear, rattle of the rattlesnake, buckskin bags of hoddentin, circles of buckskin in which are inclosed pieces of twigs and branches of trees which have been struck by lightning, small fragments of the abalone shell from the Pacific coast, and much other sacred paraphernalia of a similar kind. That the use of these cords was reserved for the most sacred and important occasions I soon learned. They were not to be seen on occasions of no moment, but the dances for war, medicine, and summoning the spirits at once brought them out, and every medicine man of any consequence would appear with one hanging from his right shoulder over his left hip.