same timbers is covered by a heavy weight of stones and earth: a tree of ordinary length is found sufficient to overlay the centre of the water; as, thus placed, it rests its ends on the projecting timbers already well secured in the midst of the masonry at the opposite banks. These, the most common of all Peruvian bridges, are constructed and kept in repair by order of the prefect of each department, who issues the same to sub-prefects or governors of provinces; and these again send out the entire community of adjacent villages to work under the direction of their respective alcaldes and regidores. There yet remains a very curious and portable bridge to be mentioned, now falling into disuse, but of which a specimen may be yet seen at Viroy, on the river Huacar, in the department of Junin: this antique relic is named “Guaro.” It is constructed by extending a single strong lazo from one side of the stream to the other, which is well secured to the trunk of a tree, or any such fixture, on the opposite banks: from this a leathern bag, not unlike in appearance to a canvass draw-bucket used aboard ship, is suspended, so as to run easily on the lazo; the passenger sits in the bag, and slides himself quietly across. Bridges of this description are said to have been exceedingly useful to the Montonera, or irregular patriot troops, during the late war that ended in the separation of Peru from Spain. Another contrivance for passing lakes and rivers in the Andes is the “balsa,” a very small canoe made of rushes. Its surface is level; and when the paddler and only one passenger steady themselves upon it, the canoe is pressed down into the water to within about an inch or two of its surface,—so, at least, was the only one we had occasion to enter; as, upon a journey during the floods of the wet season, we swam our cattle, and crossed ourselves in a balsa of rushes over the river of San Juan, on the plains of Bombon, near Pasco. The water-courses of the ancient Peruvians are traced along the chasms of rocks and sides of arid eminences in the vicinity of the coast, and in the dry intermediate glens. These aqueducts sometimes appear marvellously constructed among the most rugged crags, and in some points are raised to an astonishing elevation. They are reared from very slender foundations here and there among the now receding, now approaching, shelves of the rocks and cliffs. These piles of irregular mason-work are fabricated with small and thin stones, or light flags, leaning upon every favourable projection along the steep against the front of which the fabric rises; and all the works thus constructed are so solidly and closely united, that after the lapse of ages, and in the land of earthquakes too, they are still in numberless instances nearly perfect.