PLATE IX. 



Fig. 77. — Small metate or grinder, of sandstone. 



Fig. 78. — Grinder made of clay mortar and coarse sand, and baked as 

 hard as rock itself. 



Fig. 79. — Hammer worked from a glacial boulder; well made and much 

 worn. 



Fig. 80. — Grinder, of very fine granite. 



Fig. 81. — Grinder, of material same as figure 78. 



Fig. 82. — Grinder, made from glacial boulder. 



Figs. 83, 85. — Grinders, of fine sandstone. 



Fig. 84. — Knife blade of chert. 



