Our method of introducing critical bibliography, and the critical selection of the excerpts themselves, make it feasible to introduce quotations, not only from the latest authority in any field, but also from the great historians of the past. Thus in the case of ancient history, the classical authorities themselves are drawn upon wherever available,--Herodotus for the Persian wars, Thucydides for the Peloponnesian wars, Xenophon for later Greek history, Sallust, Cæsar, Livy, Dionysius, Dion Cassius, Tacitus, Ammianus, and the rest for Roman history; and so on indefinitely. Herodotus describes the battle of Thermopylæ; Arrian tells of the glories of Alexander; Dionysius relates the story of Virginia; Polybius shows us Hannibal crossing the Alps; Appian pictures the fall of Carthage; Josephus the fall of Jerusalem; Zosimus the fall of Palmyra. In this way a mass of first-hand matter, much of it hitherto absolutely inaccessible to the reader of English, and much more only to be found in rare and costly editions, is put within the reach of the least scholarly. But--what is most essential--such matter as this is not merely given by itself unsupported. It is supplemented by the verdicts of the latest investigators in the various fields covered. Thus, to cite but a single instance, in the history of early Greece, not merely Herodotus, Thucydides, Diodorus, Pausanias, and other ancient authorities are quoted, but the long range of modern students as well, from Mitford, Thirlwall, and Grote to Curtius, Bezold, Busolt, Geddes, Schliemann, Mahaffy, Bury, and in general the latest investigators in the field of classical archæology. Thanks to this system of checking ancient accounts with editorial criticism and other recent expert evidence, it is even practicable to avail ourselves sometimes of the writings of men who are not primarily historians, but who wrote, as so many other great authors have done, most important incidental essays on historical subjects; thus matter in the highest degree picturesque and interesting is often presented in a manner which the technical historian, however great his scientific authority, is seldom able to imitate.