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TAIU.E OF CONTENTS. 



Page. 

 Introduction — 



Soil formation 5 



Glacial histon- of Minnesota 8 



Advantages offered hy area selected 10 



Soil types studied 11 



Previous comparisons 14 



Studies in Illinois 14 



Studies in Iowa 16 



Studies in Minnesota 17 



FiKLD Work — 



Selection of fields 18 



Method of sampling- V) 



MXPKRI MENTAL 



A. Relative fineness of texture 20 



1. Proportion of coarse fragments 20 



2. Texture of fine-earth 26 



B. Lime Supply 31 



1. Carbonates 31 



2. Reaction with litmus 34 



3. Reaction by the Truog method 35 



4. Coloration of ammonia solution 37 



5. Comparison of indications obtaii led by different 



methods 39 



6. Relation of calcareousness to texture 40 



7. Relation of carcareousness to age of drift 40 



C. Inorganic Constituents — 



1. Methods of analvsis 41 



2. Silica ' 44 



3. Iron 45 



4. Alumina 45 



5. Titanium 46 



6. Lime 46 



7. Magnesia 48 



8. Phosphoric acid 49 



9. Potash 52 



10. Soda 52 



D. Organic Constituents — 



1. Volatile matter 53 



2. Organic carbon 54 



3. Nitrogen 54 



E. Color 58 



Classification of Rice County types according to thi Russian system 62 



Summary 63 



Literature Cited 66 



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