HOW CROPS FEED. 
A TREATISE ON THE 
ATMOSPHERE AND THE SOIL 
AS RELATED TO THE 
Nutrition of Agricultural Plants. 
WITH ILLUSTRATIONS, 
BY 
(Cane 
SAMUEL W: JOHNSON, M.A., 
PROFESSOR OF ANALYTICAL AND AGRICULTURAL CHEMISTRY IN THE SHEFFIELD 
SCIENTIFIC SCHOOL OF YALE COLLEGE; CHEMIST TO THE CONNEC- 
TICUT STATE AGRICULTURAL SOCIETY; MEMBER OF TRE 
NATIONAL ACADEMY OF SCIENCES. 
NEW YORK: ; 
ORANGE JUDD COMPANY, 
1891. 
eh 
