640 THE ICE AGE IN NORTH AMERICA, 



general evidence from other sources bearing upon the date 

 of the close of the Glacial epoch in this country, more fully 

 treated of in the preceding chapter. 



Since my first visit to Trenton I have studied attentively 

 all the streams situated like the Delaware with reference to 

 the glaciated area between the Atlantic Ocean and the Mis- 

 sissippi River, and can state from personal observation, as 

 heretofore detailed, that a common cause, which can not be 

 anything else than glacial floods operating while the ice re- 

 mained over the head-waters of these streams, has been at 

 work tilling them with gravel-deposits similar to those de- 

 scribed along the Delaware. Without exception, those south- 

 erly-flowing streams, whose drainage area lies to any consider- 

 able extent within the glaciated regions, are lined by exten- 

 sive terraces of the overwash gravel of the Glacial period. 



On obtaining definite information as to these facts, I at 

 once pointed out * the importance of having local observers 

 turn their attention to the discovery of palaeoliths at various 

 points in Ohio, where the glacial conditions were similar to 

 those in the valley of the Delaware at Trenton. In my re- 

 port to the Western Reserve Historical Society (p. 26) I wrote 

 as follows: "The gravel in which they [Dr. Abbott's im- 

 plements] are found is glacial gravel deposited upon the 

 banks of the Delaware when, during the last stages of the 

 Glacial period, the river was swollen with vast floods of 

 water from the melting ice. Man was on this continent at 

 that period when the climate and ice of Greenland extended 

 to the mouth of New York Harbor. The probability is, that 

 if he was in New Jersey at that time, he was also upon the 

 banks of the Ohio, and the extensive terrace and gravel de- 

 posits in the southern part of our State should be closely 

 scanned by archaeologists. When observers become familial 

 with the rude form of these palaeolithic implements, they will 



* " American Journal of Science," vol. cxxvi, pp. 7-14 ; " The Glacial 

 Boundary in Ohio, Indiana, and Kentucky " ; " Western Reserve Historical 

 Society," 1884, pp. 26, 27 ; " Ohio Archaeological and Historical Quarterly," 

 vol. i, pp. 176, 177. 



