694 THE ICE AGE W NORTH AMERICA. 



tison has been repeatedly interviewed, and his testimony is 

 uniformly coherent and explicit, to the effect that he took 

 the skull with his own hands from gravel underneath a cap- 

 ping of forty feet of black lava and in connection with drift- 

 wood. The appearance of the skull in every way corrobo- 

 rates his statement. The original incrustation shows that it 

 was not taken from a cave. The late Dr. Wyman, of Harvard 

 College, and Professor Whitney together carefully removed 

 the incrustations from the skull. Fragments of bones and 

 gravel and shells were so wedged into the cavities of the 

 skull as to satisfy them that there could be no mistake as to 

 the character of the situation in which it was found. Chemi- 

 cal analysis showed that organic matter was nearly absent, and 

 the carbonate of lime had largely displaced the phosphate ; 

 i. e., it was in a fossilized condition, 



In a visit to Sonora, California, and to Bald Mountain, where 

 the Calaveras skull was discovered, I was so fortunate also 

 myself as to run upon evidence of a previously unreported 

 instance of the discovery of a stone mortar under Table Mount- 

 ain. The mortar was found in October, 1887, by Mr. C. 

 McTarnahan, the assistant surveyor of Tuolumne county. It 

 was lying in the gravel reached by the Empire Tunnel, and 

 about a mile west of the Valentine shaft mentioned on page 

 692. This tunnel had been excavated 758 feet before reaching 

 the gravel, and the mortar was found 175 feet in a horizontal 

 line from the edge of the Table Mountain basalt, and about 100 

 feet below the surface. The object was taken out and laid 

 beside the mouth of the tunnel, and was given to Mrs. M. J. 

 Darwin, of Santa Rosa, Cal., who has given it to me. The 

 mortar is made from a bowlder of some eruptive rock, and is 

 six and a half inches through ; the hollow being about three 

 and a half inches in diameter, and about three inches deep. 



"This mortar is now in possession of the Western Reserve 

 Historical Society of Cleveland Ohio. An account of the 

 discovery was given to the Geological Society of America, at 

 Washington, in 1891. 



At the same meeting Mr. George F. Becker of the U. S. 

 Geological Survey, presented the affidavit of Mr. John H. 



