Yet the saints failed to answer that appeal. The outraged laws of nature avenged themselves with the inexorable sequence of cause and effect, and in spite of all prayer-meetings the significance of their crime against the fertility of their Mother Earth was brought home to the experience of the ruthless destroyers. In their net-work of moss and leaves forests absorb the moisture of the atmosphere, and thus nourish the springs which in their turn replenish the brooks and rivers. When the highlands of the Mediterranean peninsulas had been deprived of their woods the general failing of springs turned rivers into shallow brooks, and brook-valleys into arid ravines. Summer rains became too scarce to support the vegetation of the farm lands; the tillers of the soil had to resort to irrigation and eat their bread in a harder and ever harder struggle for existence, till vast areas of once fertile lands had to be entirely abandoned, and the arable territory of this planet was yearly reduced by the growth of an artificial desert. And while the summer drouths became more severe, winter floods became more frequent and destructive. From the treeless slopes of the Mediterranean coastlands winter rains descended like waterfalls, turning once placid rivers into raging torrents, and depriving the fields of their small remnant of fertile mould. Hillsides which in the times of Virgil had furnished pastures for thousands of herds were thus reduced to a state of desolation almost as complete as that of a volcanic cinder-field; their dells choked with rock debris, their terraces rent by a chaos of gullies and clefts, while the soil, swept from the highlands, was accumulated in mudbanks near the mouth of the river. Harbors once offering anchorage for the fleets of an empire became inaccessible from the ever-growing deposits of diluvium. Yearly mud inundations engendered climatic diseases and all-pervading gnat swarms. Insectivorous birds, deprived of their nest shelter, emigrated to less inhospitable lands, and the scant produce of tillage had to be shared with ever-multiplying legions of destructive insects. Along the south coasts of Italy the shore-hills for hundreds of miles present the same dreary aspect of monotonous barrenness. Greece is a naked rock; forests have almost disappeared from the plains of Spain and Asia Minor; in northern Africa millions of square miles, once teeming with cities and castles, have been reduced to a state of hopeless aridity. The Mediterranean, once a forest-lake of paradise, has become a Dead Sea, surrounded by barren rocks, and sandy or dust clouded plains. According to a careful comparison of the extant data of statistical computations, the population of the territory once comprised under the jurisdiction of the Cæsars has thus been reduced from 290,000,000 to less than 80,000,000, i.e., from a hundred to less than thirty per cent. In other words, an average of seventy-eight in a hundred human