ACKNOWLEDGMENTS OF ILLUSTRATIONS 



Yerkes Observatory — Fig. 1. M. C. Ford, Bowling Green, Ky. 

 Figs. 4, 34 and 199. International Harvester Co. — Fig. 214. 

 L. W. Brown, Photographer, U. W. — ^Fig. 30 and frontispiece. 

 American Chemical Company, Boston — ^Figs. 32, 142 and 169. 

 JanesviUe Machine Company, Janesville,Wis. — ^Figs. 66, 68, 69, 71, 

 74, 85, 87, 92, 106, 107, 112, 143, 210 and 213. Deere and Company, 

 Moline, III. — ^Figs. 73 and 88. Moline Plow Company, MoHne, 

 lU.— Fig. 160. D. S. Bullock, U. W.— Fig. 144. Allis-Chabners 

 Mfg. Co., Milwaukee — ^Fig. 155. Rockfield Products Company, 

 Milwaukee — ^Fig. 154. Jeffrey Mfg. Company, Columbus, Ohio — 

 Fig. 157. J. S. Donald, Mt. Horeb, Wis.— Fig.159. Mark W. Potter, 

 Belhaven, N. C.-^Figs. 195, 196 and 204. Mosier and Gustafson, 

 authors of Soil Physics and Management — ^Figs. 18, 64, 67, 80, 

 93, 98. John W. Lloyd, author Productive Vegetable Garden- 

 ing — ^Fig. 95. Kary C. Davis, author Productive Plant Hus- 

 bandry—Fig. 93. U. S. Dept. of Agriculture — Figs. 170 to 

 187, inclusive. 



