The fields on these plantations and farms are generally divided by walls, called _tapiales_: these are formed of large square masses of clay or earth, sometimes mixed with stones, each being about four feet long, two thick, and two broad, and are called _adobones_; the walls are sometimes four and sometimes six feet high, being composed of two or three layers of adobones. They are made by laying a frame of wood on the ground, composed of two sides and one end, the sides being secured at the other by thongs of raw hide; the earth on one side the box or frame is then wetted with water, dug over once or twice, and put into the frame, _adobera_, where it is trodden hard, or beaten with a heavy rammer; more earth is thrown in, and again pressed down, until the frame is quite full, when the top is smoothed over with a wooden trowel and some water. The frame is removed by untying the thongs, which allows the sides of the adobera to open a little, and to separate freely from the adobon, which is smoothed with the trowel or hand with a little water; the frame is now placed with its open end to the adobon which is finished, and another is made and placed adjoining to it by the same process. When a second or third tier is raised, two pieces of plank or scantling are laid on the lower adobon, to support the frame, which is filled as before; the scantlings are then drawn out and the frame removed; the holes are sometimes filled up, and sometimes left open. When stones are mixed with the clay or earth they are usually placed along the sides of the frame, the centre being filled up with earth, to which cut straw is occasionally added, particularly when the soil is rather sandy. These fences are very durable; a ditch is formed on one or both sides, according to the will of the master, and the earth dug out serves to make the wall, and at the same time secures it from being undermined by the water, which would be injurious to the foundation. In those parts of Peru where it rains, small bundles of brush wood are put across the top of the tapial, and clay laid on them to prevent the rain from penetrating: if tiles were substituted they would answer much better. I have been rather minute in describing these walls, being convinced that with a few improvements they would be found preferable to some fences used in England; indeed the easy method of building them deserves to be communicated to those who are in the habit of constructing fence walls instead of hedges, a common practice in our hilly countries. As a proof of their duration, many of these clay fences are now standing on the coast of Peru, and of those cased with stone in the interior, built more than three centuries ago, by the indians, before the Spaniards discovered their country.