A complete world history should, properly speaking, begin with the creation of the world as man’s habitat, and should trace every step of human progress from the time when man first appeared on the globe. Unfortunately, the knowledge of to-day does not permit us to follow this theoretical obligation. We now know that the gaps in the history of human evolution as accessible to us to-day, vastly exceed the recorded chapters; that, in short, the period with which history proper has, at present, to content itself, is a mere moment in comparison with the vast reaches of time which, in recognition of our ignorance, we term “prehistoric.” But this recognition of limitations of our knowledge is a quite recent growth--no older, indeed, than a half century. Prior to 1859 the people of Christendom rested secure in the supposition that the chronology of man’s history was fully known, from the very year of his creation. One has but to turn to the first chapter of Genesis to find in the margin the date 4004 B.C., recorded with all confidence as the year of man’s first appearance on the globe. One finds there, too, a brief but comprehensive account of the manner of his appearance, as well as of the creation of the earth itself, his abiding-place. Until about half a century ago, as has just been said, the peoples of our portion of the globe rested secure in the supposition that this record and this date were a part of our definite knowledge of man’s history. Therefore, one finds the writers of general histories of the earlier days of the nineteenth century beginning their accounts with the creation of man, B.C. 4004, and coming on down to date with a full and seemingly secure chronology.