Farmers of Forty Centuries 



A History of the Permanent Agriculture in China, Korea, and Japan 



By F. H. KING, D.Sc. 



Late Professor of Agricultural Physics, University of Wisconsin 



Written by one of America's foremost Agriculturists, who made a close 

 study of the methods by which the Chinese have supported* 500,000,000 

 people for four thousand years on an area smaller than the improved farm 

 land of the United States. 



"No more important practical contribution to geographic knowledge has 

 been published in many years than 'Farmers of Forty Centuries.' " — Review. 



A book of strong interest for the botanist and agriculturist, as well as for 

 the practical man and the student, containing 450 pages and 248 illustrations. 



The price, postpaid, is $2.50. Orders should be sent to 



Mrs. F. H. King, 



Madison, Wisconsin. 



STOPPER CLAMPS 



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Each $3.50— Per Ten $33.00 

 THE PLANT WORLD _ _ . Tucson, Arizona 



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