316 THE TROGLODYTES. 



labor or means of dofense. IJo iabricated tools and weapons of war- 

 fare, out of various hard materials, such as the bones, teeth, and horns 

 of animals, and above all of stone, especially flint, and this is the reason 

 why in the history of man the name of Stone age has been given to the 

 whole i)eriod which preceded the use of metals. 



This age of stone still continues among certain savage tribes, and it 

 came to an end with the most anciently civilized nations at a period 

 only a very little anterior to historic times. It therefore includes almost 

 the entire duration of the existence of humanity. Now, the mode of 

 fabrication, the lorm and nature of these iustruments, necessarily varied 

 during this immense period, with the needs, the kind of life, and the so- 

 cial state of the men who employed them ; and when we renumiber that 

 hard substances like stones may be preserved for an uulimited period in 

 the ground, we comprehend that these remains of human industry con- 

 stitute iiu>ffaceable records of the past, chronological documents of the 

 utmost importance. 



The dates established by prehistoric archa3ology accord very well, and 

 sometimes coincide, in a most remarkable manner, with those of paleon 

 tology and stratography. Just as certain species of animals have con- 

 tinued from the earliest Quaternary times, so certain Ibrms of flint instru- 

 ments have been perpetuated through several archivological ages. Such 

 are the elongated i)ieces of stone, with their two edges sharpened, and 

 one face cut with two sides, while the other has but one, called knives. 

 The small knives of obsidian, still in use among the aborigines of Mex- 

 ico, and the flint knives, which our ancestors of the Bronze age frequently 

 deposited in their sepulchers, are very similar to those of the age of the 

 nmnnnoth. l>ut this is an exceptional case ; in general, inehistoric iu- 

 struments have from age to age undergone various modifications. 



I cannot attempt here to mention, still less to describe, the numerous 

 iustruments of each period : axes, knives, points of lances, or of arrows, 

 scrapers, hammers, &c. Geologists frequently, as we have seen, deter- 

 mine and designate an entire launa by a single characteristic species. 

 JSo arclurologists distinguish tlie difterent periods of the Stone age by 

 the instrument the most characteristic of each of them. 



A precise determination of these periods and of their number is not 

 possible; for the flint instruments have, during the same period, under- 

 gone dilVerent changes in dil'ferent localities, but a general reduction into 

 three has been made by M. de ^Mortillet of the archteological divisions of 

 the Quaternary period. 



1. The most remarkable type of the first Quaternary division is the 

 so-called iSaint Adieul ax. (See Figs. 1 and 2.) It is of flint, of variable 

 size, always quite large, longer than wide, thick in the middle, sharp- 

 ened at the edges, with one end pointed, or rather orgival, while the other 

 is rounded; but its most distinguishing characteristic is that its two 

 faces or sides are shaped ; these are more or less convex, and more or 

 less symmetrical. This type abounds at Saint Acheul, near Amiens, in 

 the valley of the Somme ; hence its name; but it is found in almost all 



