The country of Peru has three distinct sections longitudinally: the Coast region, the Sierra, and the _Montaña_--the first well known and fairly settled, the second with the greater population, the third having much the largest area, but thinly peopled chiefly by wild Indians, and not thoroughly explored. The term _montaña_, one of the Spanish words for mountain, in Peru is generally applied to the forest region on the eastern slope of the Andes and the plains beyond; the plateau and mountain section with the narrow valleys included form the sierra. THE COASTAL REGION The coast of Peru is a strange one, presenting to the uninformed traveler a series of surprises. One expects to find it hot in the tropics, at least at sea level; but on ship-board sailing south when 3° below the equator, at least in the winter season, which it must be remembered is during our summer, warm clothing if not heavy underwear is necessary with blankets at night. One is amazed too to find at Paita (for some steamers the first port of call), a real desert, in striking contrast to the rich vegetation near the Guayas River. The chief reason for the comparatively cool temperatures experienced on the entire coast of Peru is found in the Humboldt or Antarctic current which flows from the icy realms far south, with chilling effect, close along the shore to the region of the equator, where near the most western points of the continent it turns west across the Pacific. The high mountains too, here quite near the shore, have some cooling influence and are a prime cause of the existing desert. The hot moist winds, which in the equatorial regions blow west from the Atlantic dropping more or less of their vapor on the way, on reaching the highest Andes lose all the rest, as every bit of the moisture is condensed by the freezing mountain sides; the average height of the range in Peru is above 17,000 feet. After passing the mountains the winds descend cool and dry to the plains. The damp chilly winds which come north with the Antarctic current, as they blow over the shore, find this warmer than the ocean, so the moisture is not condensed. Thus it is that the coast of Peru with that of northern Chile, being practically rainless, is called a desert, though in Peru it is not wholly barren. From her mountains 58 streams come down toward the Pacific, though not all reach the ocean or last throughout the year. In these valleys there is green, a beautiful and welcome contrast to the desert; in most of them are irrigation and agriculture. Because the nitrates have not been washed out of the soil by rain, where a suitable water supply can be provided, the land constitutes one of the finest agricultural regions on the globe.