About this period of dire suffering of the Egyptians from pestilence, the first dreadful epoch of Spanish epidemiology is recorded as having commenced; the date, however, has been variously given. By some writers it is fixed about the time of David, 1017 B.C., when 70,000 persons were destroyed in three days by pestilence; by other writers it is stated to have commenced amongst the Spanish 1100 B.C. There were _twenty-five_ years of drought in Spain without interruption; springs were dried up; rivers became fordable, their waters being almost stagnant; there was neither pasture for beasts, nor fruit for man; so great was the barrenness of the land, that there was scarcely anything green to be found, except some few olive-trees on the banks of the Ebro and the Guadalquivir: such, says the historian, was the melancholy state of ancient Spain, “full of dreadful mortalities, plagues, and miseries of every description, which, with emigration to other lands, nearly depopulated our country.” The Greek poet, Homer, describes the causes of the pestilence which attacked the armies at the siege of Troy as being attributable to the extreme heat of the weather and the unfriendly seasons. He styles the sun Apollo: “On mules and dogs th’ infection first began, And last the vengeful arrows fix’d on man; But let some prophet or some sacred sage Explore the cause of Great Apollo’s rage.” Thucydides, another celebrated Greek historian, describes a similar condition of the atmosphere with physical irregularities, as causing an awful pestilence at Athens: τεκμήριον δὲ τῶν μὲν τοιούτων ὀρνίθων ἐπίλειψις σαφὴς ἐγένετο, καὶ οὐχ ἑωρῶντο οὔτε ἄλλως οὔτε περὶ τοιοῦτον οὐδέν· οἱ δὲ κύνες μᾶλλον αἴσθησιν παρεῖχον τοῦ ἀποβαίνοντος διὰ τὸ ξυνδιαιτᾶσθαι. Lucretius, in imitating Thucydides, thus expresses himself: “Nec tamen omnino temere illis solibus ulla Comparebat avis, nec noctibus secla ferarum Exibant sylvis; languebant pleraque morbo Et moriebantur; cum primis fida canum vis Strata viis animam ponebat in omnibus ægram; Extorquebat enim vitam vis morbida membris.” “No longer birds at noon, nor beasts at night, Their native woods deserted; with the pest Remote they languish’d and full frequent died; But chief the dog his generous strength resign’d, Tainting the highways, while the ruthless bane Through every limb his sickening spirit drove.”