Rlv. Bas. Sur. 

 Pap. No. 25] 



JOHN H. KERR RESERVOIR BASIN — MILLER 



79 







/NCHES 



Figure 9. — Chippers or "Ecrasoir ou retouchoirs" (after de Mortillet, 1881). 



as though the maker understood both his technique and the quality 

 of the stone being worked upon. Four distinct sizes were recovered. 

 The largest specimen measures 70 mm. in length, 24 mm. in maximum 

 width, and 11 mm. in thickness. The other three measured 49 mm., 

 43 mm., and 29 mm. in length respectively ; 23 mm., 21 mm., and 20 mm. 

 in width respectively ; and 10 mm., 10 mm., and 10 mm. in thickness 

 respectively. It will be noted that the thickness of all four was prac- 

 tically uniform, being aromid 10 mm. Widths seemed to be pretty 

 well standardized, being between 21 and 22 mm. The only real variant 

 occurs in the length factor. Three of these objects were made out of 

 chert, while the fourth was made out of rhyolite. (For further dis- 

 cussion see "Flaking tools" in this report pp. 95-96.) 



In the manufacture of snub-nosed scrapers a number of moderately 

 thick and flat trigonal flakes, the results of hinge fractures, were first 

 struck from a core. These flakes constitute the basic form out of 

 which scrapers were fashioned. To convert these trigonal flakes into 

 scrapers, the hinge joint, which is at the widest lateral edge, would 

 have to be properly chipped, starting with the edge closest to the ven- 

 tral surface and chipping at an obtuse angle toward the dorsal surface 

 to create an edge capable of scraping. If cliipping is only applied 

 to tliis particular surface, a cutting edge is produced that may be given 

 greater keenness by additional retouching. This form is usually and 

 roughly triangular in cross section and outline. Another form, sim- 

 ilar to the former, can be made by working all lateral edges and 

 blunting the basal tip so that it is more trapezoidal in cross section. 

 Still another form would result by the formation of a "graver tip 

 or tips" adjoining the scraper edge and a side, a form known as a 

 "spurred" scraper. Variations between these basic forms wiU result 

 in a number of subforms. 



568192—62- 



