CLIMATE. Though the island is in the tropics. it is also under the regime of the persistent northeast trade winds, which temper the heat. The topography causes local climatic differences and the natives even speak of the 'rigors of winter' in the upper altitudes. The annual range of temperature is from 100°, which is very rare, to 50', which is sometimes reported among the mountains. The mean annual temperature at San Juan, on the north coast. ranges from 75° to 82°. The climate would seldom be op pressive if it were not for the constant high humidity. Rain falls almost daily, the annual precipitation at San Juan averaging 60 inches. Nearly two-thirds of the precipitation falls in the summer and autumn. The rain increases from San Juan eastward, is heaviest on the high lands, which arrest much of the precipitation, so that the south slope of the island is much drier, and in some regions irrigation is necessary for the cultivation of crops. Among the causes
that interfere with agricultural prosperity are hurricanes. Between 1515 and 1899 eighteen very destructive hurricanes occurred. The espe cially disastrous hurricane which visited the island on Aug. S, 1899, caused large loss of life and immense damage to crops, and 250.000 per sons were compelled for some time to depend upon the Government for food.
Near the ocean the soil is quite sandy; it be comes loamy as it extends inland, and gradually changes from a•sandy to a clay loam on ascending the lower foot hills. The soil of most of the coastal plains is rich alluvium, which gradually merges into the clay loam of the hills. The fer ruginous clay of the mountains is a source of abundant supply of plant food.