8 



History of Hingham. 

 Estimated Length of Geological Periods. 



It is proper to state here that investigations within a few years 

 past by Dr. G. Frederick Wright, the author of the " Ice Age in 

 North America," Warren Upham, and other geologists who have 

 made special study of the phenomena of the Glacial Period, have 

 satisfactorily determined that all that has happened on the surface 

 since that period may not have required more than from ten to 

 fifteen thousand years. When the above table was prepared, much 

 less was known of glacial action than now. 



