Vol.20. AUGUST 1885. No. 123. 



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N° 123.— AUGUST 1885. 



WITH THREE PLATES. 



Illustrative of Dr. J. D. Dana's Paper on the Origin of Coral Eeefs and 

 Islands, Dr. J. A. Fleming's on the Use of Daniell's Cell as a 

 Standard of Electromotive Force, and Mr. J. Buchanan's on the 

 Thermoelectric Position of Carbon. 



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