ETHNOLOGY. 319 



new arcbffiolog'ical era. Hitherto these iustruments were made by per- 

 cussion or by pressure; although, it is true, some implements of sec- 

 ondary use were rounded into shape by friction, but the flint tools and 

 weapons were always chii)ped. In the era upon which we are now en- 

 tering these implements were made in the same way, but the flint was 

 j)olished, and the polished ax, too well known to need description, be- 

 came the principal auxiliary of man. (See Fig. 7.) 



This ax characterized the period of polished stone or the neolitliic 

 period winch terminated the stone age, and consequently lasted until 

 the introduction of the metals. 



All the periods which precede the appearance of the polished ax con- 

 stitute the period of stone, also called the archa^olithic, or, rather, the 

 paleolithic period. 



The various phases of the age of chipped stone succeeded each other 

 progressively, and by almost insensible transitions, like the correspond- 

 ing geological periods ; but the change to the period of polished stone 

 was much more abrupt. Its commencement coincides exactly with the 

 disappearance of the reindeer, that is with the end of paleontological 

 time, and with the beginning of the present geological era. It coin- 

 cides also with a complete change in the social condition of man, with 

 the domestication of the dog, with the adoption of pastoral life, marked 

 by the domestication of several herbivorous animals, and also with the 

 iutrodu<;tion of agriculture. Thus many centuries passed until the 

 appearance of the bronze, which put an. end to the stone age. The 

 length of the period of polished stone was very great; the entire dura- 

 tion of historic time was nothing in comparison, and yet it was immeas- 

 urably shorter than any of those v/hich form the age of chipped stone. 



We have thus examined the succession of pr<^-historic ages from the 

 commencement of the Quaternary period, under the triple point of view 

 of stratigraphy, paleontology, and archaeology, and we have obtained 

 three series of dates which, if not altogether i^recise, are sufficiently 

 approximate to form the following table, which may serve as a review : 



Stratigrapliical periods. 



Paleontulogical periods. 



Arcbaiological jieriods. 



t? I Lower strata of valleys uudis 



« ,-• 



g o ) tnrbed. 



■^ o I Median strata 



C" [ Upper strata 



^3* }Eece.t deposits 



Age of luarumoth. 



lutenuediate age 

 Age of reindeer. . 



Actual fauua 



The St. Achcul as. 



Lance-head of Aloustier. 

 Lance-head of Solutre. 



The polished ax. 



II. — Successive ja)CAlities of the troglodytes of the Ye- 



ZERE. 



We now possess the knowledge requisite to assign a place in time 

 to the troglodytes of the valley of the Vezere. In their numerous 

 localities not a single polished ax has been found; their industrial im- 

 plements belong to the age of chipped stone, and are, therefore, anterior 



