PERU 337 current price for the better qualities in Eu- rope, would represent $675,000,000. Other great sources of wealth are the saltpetre and borax of the pampa of Tamarugal in Tarapaca, though the former is too deliquescent to be used in the manufacture of gunpowder. It is calculated that the saltpetre grounds embrace an area of 50 square leagues. In 1860, 77,000 tons were exported from Iquique. Borax is also shipped, in spite of the government pro- hibition. In 1873 the saltpetre was constituted a government monopoly; but in 1874 it was contemplated to abandon the monopoly, and apply an export duty. In the latter year 320,- 000 tons were shipped. The appearance of the Tarapaca desert resembles that of a coun- try after snow, before the last dirty patches are thawed, from being covered by a thick crust of common salt and of a stratified salifer- ous alluvium, seemingly deposited as the land slowly rose above the sea level. The salt, which is white, very hard, and compact, oc- curs in water-worn nodules projecting from the agglutinated sand, and is associated with much gypsum. The saltpetre beds follow for a distance of nearly 150 m. the margin of a great basin or plain 3,300 ft. above the sea, which from its outline Darwin pronounces to have once been a lake or more probably an inland arm of the sea, as he infers from the presence of iodic salts in the saline stratum. A variety of precious stones are found in Peru, which is likewise remarkable for the number of its thermal and mineral springs, many of which are medicinal. The climate, on the whole re- garded as tolerably healthy, differs essentially in the four great topographical divisions : the coast region, the sierras, the table lands, and the eastern plains. The coast is usually called the rainless region ; indeed, with the exception of Iquique, where a light shower falls once in very many years, rain is unknown from the river Loa to Cape Blanco, a phenomenon attributed to heated air currents ascending from the vast sand wastes, which in some places are from 45 to 60 m. in width. During the winter, from May to November, there are dense drizzling mists. The hills about Lima, a little more than 1,000 ft. above the sea, are carpeted with moss enamelled with beautiful yellow lilies (aman- cdes), a vegetation indicative of a much greater degree of moisture than at a corresponding altitude in Tarapaca. Northward of Lima the climate grows gradually damper; and in the extreme northwest, beginning from the paral- lel of Cape Blanco, rains are as copious and the forests as dense as in the littoral region of Ecuador. Toward December, when the dry season has fairly set in, the weather, except for an interval at noon, is for the most part cool and delightful. The cold current which runs along this coast from the seas adjoining Cape Horn, and the temperature of which is on an average 8 lower than the mean annual tem- perature of the atmosphere at Callao, tempers the heat on the shores of Peru. The mean heat at Callao does not exceed 60, and the mercury is frequently as low as 55. At Lima, 6 m. inland from Callao, and 600 ft. higher, it never falls below 60 in winter, and seldom rises in summer above 80. The hottest day ever known in Lima was in February, 1791, when the thermometer marked 96. In Piura, the extreme N. TV. province of Peru, the tem- perature ranges in summer from 80 to 96, and in winter from 70 to 81. The situation of the coast region, between the influences of the sea on the one side and the lofty moun- tains on the other, renders the climate tem- perate. The rainy season in the sierras, the table lands, and the eastern plains corresponds to the period of drought on the coast. The watery vapors are then wafted from the latter by the sea breeze to the high regions, where they are condensed and fall in heavy showers ; whence the phenomenon of the coast rivers drying up in winter and pouring down copious floods in summer. During the greater part of the year the winds on the coast blow from the south, varying from S. S. E. to S. W. ; in the winter months breezes from the north some- times occur. At some distance from the shore the S. E. trade wind prevails, with greatest strength in winter. Lightning is sometimes seen on the coast of Peru, but thunder is never heard, and storms are quite unknown. In the sierras or highlands and the table lands there is a considerable range of temperature, between the rain line, at about 7,000 ft. above the sea, and the snow line. About 9,000 ft. above the sea the average temperature is 60, varying little throughout the year, and the seasons are only distinguished as the wet and the dry, the former of which lasts from November to May. The climate of the eastern plains is hot and moist. The moist winds which blow from the Atlantic, over the plains watered by the Ama- zon and its tributaries, are stopped in their progress toward the Pacific by the Andes, and accumulate clouds which descend in heavy rains accompanied by thunder storms of great violence. These copious rains cause such an excess of moisture that the region is very un- healthy, and few individuals among the Indian tribes scattered along the banks of the rivers reach the age of 50 years. Ague is unknown in the interior ; but on the coast both foreign- ers and natives, at all seasons, suffer severely. A remarkable phenomenon occurs periodically along the coast from Callao N. as far as Lam- bayeque, a distance of about 500 m., consisting of a fetid, nauseous, and depressing odor, ac- companied by changing colors of the water, and a curious discoloration of the white paint both outside and inside of the shipping. The- painter, as the phenomenon is called, has by some been attributed to miasmatic effluvia per- colating through the land from the Andes, and by others to the decomposition of the excreta washed into the bays at the embouchures of .the rivers; whatever the cause may be, the repulsive element most sensibly perceived is
