We have now arrived at a point of time very far removed from that of the dweller in caves, the man who was contemporary with the great bear and the mammoth! Scarcely, perhaps, have we preserved a reminiscence of those mighty quadrupeds whose broad shadows seem to flit indistinctly across the dim light of the quaternary epoch. Face to face with these gigantic creatures, which have definitively disappeared from the surface of our globe, there were, as we have seen, beings of a human aspect who, dwelling in caves and hollows of the earth, clothed themselves in the skins of beasts and cleft flakes of stone in order to form their weapons and implements. We can hardly have failed to feel a certain interest in and sympathy with them, when tracing out the dim vestiges of their progress; for, in spite of their rude appearance, in spite of their coarse customs and their rough mode of life, they were our brethren, our ancestors, and the far-distant precursors of modern civilisation. We have given due commendation to their efforts and to their progress. After a protracted use of weapons and implements simply chipped out of the rough flint, we have seen them adopt weapons and instruments of polished stone, that is, objects which had undergone that material preparation which is the germ of the industrial skill of primitive nations. Aided by these polished-stone instruments, added to those of bone and reindeer's or stag's horn, they did not fear to enter into a conflict--which every day became more and more successful--with all the external forces which menaced them. As we have seen, they brought under the yoke of servitude various kinds of animals; they made the dog and the horse the companion and the auxiliary of their labour. The sheep, the ox, and other ruminants were converted into domesticated cattle, capable of insuring a constant supply of food. After the lapse of ages metals made their appearance!--metals, the most precious acquisition of all, the pledge of the advent of a new era, replete with power and activity, to primitive man. Instruments made of stone, bone, reindeer or stag's horn, were replaced by those composed of metal. In all the communities of man civilisation and metals seem to be constant companions. Though bronze may have served for the forging of swords and spears, it also provides the material for implements of peaceful labour. Owing to the efforts of continuous toil, owing also to the development of intelligence which is its natural consequence, the empire of man over the world of nature is still increasing, and man's moral improvement follows the same law of progression. But who shall enumerate the ages which have elapsed whilst these achievements have been realised?