TABLE OF CONTENTS. xiii 



AGRICULTURE AND RURAL ECONOMY Continued. 



Assimilation of Nitrogen by Leguminous Crops Aided by Potassic 



Fertilizers Page 359 



Is the Free Nitrogen of the Air a Source of the Nitrogen Assimi- 

 lated by Plants ? 3G0 



Is the Combined Nitrogen of the Air the Source of the Assimilated 



Nitrogen? 30 1 



Nitrification by Electrical Discharges 302 



Is the Nitrogen Combined under the Influence of the Soil a Source 



of the Supply Assimilated by Plants ? 302 



Best Forms of Nitrogen for Plant-Food 303 



Source of the Carbon of Plants 304 



Phosphoric Acid as the Food of Plants 305 



Lime as Plant-Food 305 



Root-Development of Plants 300 



Manures 300 



Phosphatic Fertilizers 300 



Nitrogenous Fertilizers 307 



Fish-Scrap 308 



Fermentation of Fish-Guano 308 



Potassic Fertilizers 308 



The Need of Better Information about Fertilizers 371 



Composition of Plants 372 



Fodder Corn and Sweet-Potatoes 372 



Buckwheat Straw 372 



Pumpkins, Squashes, Broom-Corn Seeds, Weeds, etc 373 



Sugar-Beet Culture and Beet-Sugar Making 373 



Nutrition of Animals. Stock-Feeding 374 



Sources of the Fat of the Animal Body 374 



Effect of Fodder upon Milk Production 375 



Changes in the Milk during the Period of Lactation 370 



General Conclusions from Experiments on Effects of Food 

 upon Milk Production 370 



Other Feeding Experiments 377 



The Digestive Capacity of Horses 377 



Digestion of Foods by Swine 378 



Digestion of Foods by Sheep 378 



Value of Animal Waste as Food for Stock. Fish-Scrap 379 



Practical Inferences from Feeding Experiments 380 



ENGINEERING. By William H. Waul, Ph.D., Philadelphia, Pa 381 



Railroads 381 



The Canal Across the American Isthmus 3*2 



The Mississippi Jetties 383 



Other American Engineering Works 384 



