24 THE POPULAR SCIENCE MONTHLY. 



the human relics were found in deposits representing the closing 

 episodes of the later epoch of Quaternary cold. 



There are several cases in which traces of human activity 

 have been reported from older deposits, but in which the discov- 

 eries are not so well authenticated. E. g., there is Dr. Koch's 

 well-known record of the finding of mastodon remains in the 

 Osage Valley, Missouri, associated with human implements and 

 traces of fire, in deposits probably contemporaneous with those of 

 the earlier ice-sheet ; but the geologic relations have never been 

 clearly made out, and the verity of the discovery has always been 

 (perhaps unjustly) questioned. The finding of a fossilized human 

 bone at Natchez, Mississippi, apparently associated with an early 

 Quaternary fauna, is equally well known ; but the attendant cir- 

 cumstances were not such as to carry conviction to the minds of 

 contemporary students. Lewis, also, has described a paleolithic 

 implement from aqueo-glacial gravels at Philadelphia ; but he 

 did not personally witness the discovery, and was not certain that 

 the object came from the older (earliest glacial) and not the newer 

 (latest glacial) gravels. It is significant that in all these cases 

 the testimony is internally defective ; and, since its acceptance 

 would many times multiply human antiquity as established by 

 collateral evidence (as clearly shown in Fig. 1), it would seem 

 especially wise to reserve judgment upon it. 



There are other cases in which human remains have been 

 found in such position as to indicate great antiquity measured in 

 years — e. g., the shell-heaps of Damariscotta River in Maine and 

 St. John's River in Florida, representing a fauna now extinct or 

 displaced ; the enormous shell-heap at San Pablo on the Bay of 

 San Francisco, which e^ddently represents a vast period of build- 

 ing ; the shell-beds and superimposed deposits of the Aleutian 

 Islands, which have been shown by Dall to represent at least 

 three thousand years of accumulation, etc. ; but in none of these 

 cases is it possible to reduce the historic time-units to definite 

 geologic time-units. 



There are still other cases in which human relics have been 

 reported from deposits of considerable geologic age — e. g., in Cala- 

 veras County, California, near Golden, Colorado, etc. ; but, while 

 the arch^eologic evidence would seem conclusive in at least one 

 of these instances, it is impossible to confidently transmute the 

 paleontologic record of the age of the deposits into the physical 

 record which alone is sufficiently refined for the measure of hu- 

 man development ; and it would thus seem wise to reserve judg- 

 ment in these cases, also, with respect to the correlation of the 

 deposits as well as to the association of the relics. 



Excluding all doubtful cases, there remains a fairly consistent 

 body of testimony indicating the existence of a widely distributed 



