MAPS AND ILLUSTRATIONS XV 



PAGE 



Soil Bacteria * 315 



Southern Cotton Field 316 



Bacterial Nodules on Bean Roots 318 



Anthill. 319 



Molehills . - . . 319 



Lumpy Soil 320 



Adobe Soil . . . . 321 



Mud Cracks . .'..... . . . . .322 



Prairie Scene . ...... 322 



Alfalfa Root . . . ; .."..' ./ 323 



Rice Swamp . . v . 324 



A Natural Spring 326 



An Artesian Spring . ., 327 



Dry Farming in Egypt . . 328 



Kaffir Corn . . . , . . 329 



Irrigation in Squares ..' , 330 



Irrigation in Furrows . 331 



Alkali Soil .v 332 



Reclaiming Alkali Soil in the Sahara 333 



Roman Plowing . . .,.-. . . . ... . . 333 



Labor-saving Machinery 334 



Good Soil, a Truck Farm . , 335 



East End of the Assuan Dam across the Nile 336 



Results of a Sudden Flood 337 



A Cypress Swamp in Louisiana before Drainage .... 337 



Cypress Swamp Reclaimed ;<;.. . . . . . . 338 



Bad Lands of Dakota . . . . ... . . .339 



Bad Forestry ... ... .'.'. . .340 



Bad Forestry . . ... ' . . . . . 341 



Bad Forestry ./. . . . . . ... . .342 



Good Forestry . . . . 



Good Forestry . . . . . . . . . . - 344 



A Lake Mirror , . . v;.. . . - . : . :; , . . 348 



A Reflection Engine '' 351 



Telescope Equipped with a Spectroscope . . . . . . 359 



Lick Observatory . ... . . . , . . . . 360 



Hospital Ward . . . > .'.'. . . - 362 

 An Old Whale Oil Lamp .... V ^- .: . i . . 363 



The Grizzly Giant . . ...... . '. . -367 



A Typical Plant ' ' -368 



Roots Securely Holding the Tree Erect . . . . . 369 



A Pine Tree 374 



A Splendid Tree Developed under Ideal Conditions . . .376 



