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Proceedings of the Royal Society of Edinburgh. [Sess. 
waves the corresponding differences obtained from the values adopted by 
Wiechert and Geiger, a method which is open to criticism. 
It should be remembered that all these tables are prepared from 
averages of statistics not all of the same accuracy. The data from any 
one earthquake never agree throughout with these average tabulated 
values, and no doubt as time goes on considerable corrections will have 
