a river of Chili, in the department of Santiago, rises in the Andes, between the volcano of the same name and the Peak of Tupungato, flows westward, and, after a course of 160 miles, falls into the Pacific. For about one-third of its course, the river flows in narrow ravines among the high mountain ridges of the Andes; but in the lower part of its course it traverses the S. portion of the plain of Santiago, which it waters by means of a canal. Its waters are much impregnated with salt; and dash along with an impetuosity which no ordinary bridge could withstand. It is therefore crossed only by swinging bridges of ropes, on the model of those of the ancient Peruvians. The Rio de Colina, from the plain of Santiago, falls into this river. In the plains traversed by the Maypu, a great and decisive victory was gained in 1818, by the republicans under San Martin, over the royalists, which put an end to the Spanish dominion in Chili.