BULLETIN OF THE 



"Humus." Its origin, and influence on the physical proper- 

 ties of Soils. 

 Summary of functions of physical soil ingredients, 



CHEMICAL COMPOSITION, AND ANALYSIS OF SOILS. 



Elements concerned in formation of Soils. 



"Whence derived. 



Nutritive and inert Soil ingredients. 



Ash ingredients of Plants; derived from Soil; Carbon 

 from Air, Nitrogen from both. 



A priori view of Soil analysis Composition of crops. 



Fallacies. Distinction between available and unavailable 

 portion of nutritive soil ingredients. 



Difficulties, and attempts to overcome them. 



Causes of failure rejection of soil analysis. 



Professor Johnson's arguments. 



Discussion of objections. What soil analysis may fairly 

 claim to do for practice, in application to virgin soils. 



To identify and distinguish soils, thus making past ex- 

 perience available in new regions. 



To determine their prominent characteristics, both phys- 

 ical and chemical. 



To show abundance, scarcity or absence of important 

 soil ingredients, thus indicating the general adapta- 

 tion, permanent value, and cheapest mode of im- 

 provement, or maintenance of fertility. 



Always provided, that systematic observation on the spot, of all 

 circumstances influencing cultivation, and comparative 

 examination' of soils of similar origin, be kept in view. 

 Mere columns of figures of little use. 

 Taking of Specimens details. 



Methods of chemical analysis; elements to be determined. 



Choice of solvents. General Analysis Details. 



Determination of Phosphoric Acid. 



Determination of "Humus" and Nitrogen. 



FUNCTIONS OF THE SEVEEAL CHEMICAL SOIL INGREDIENTS, AND THEIR 



CONDITION IN THE SOIL. 

 Outlines of Vegetable Physiology. 



Experiments on growth of plants in soils devoid of or- 

 ganic matter; in solutions. 



Object of the course mainly the consideration of the 

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