FOURTH ANNUAL YEAR BOOK — PART VI. 377 



three inches below the surface, while the freshly harrowed land on 

 which the second planting was made had a temperature of 50 degrees 

 at the same depth. This shows that disking and harrowing had the ef- 

 fect of warming up the soil 5 degrees in five days. 



Some years ago the writer had a large area of land in another state 

 to be planted to corn. It rained almost c'ontinuously until May 15th, 

 and the soil was stiff and cold. It was so late in the season when the 

 rains stopped that something had to be done immediately to prepare 

 the ground for planting. We started disk harrows as soon as the sur- 

 face became dry. although the horses' feet sank three to five inches in 

 the mud. If this disked land had been allowed to become dry it would 

 have been very lumpy. Just as the disked soil began to get dry enough 

 to crumble it was cross-disked, and this left it dry and mellow enough 

 for immediate planting. 



A small field was left as a test until it became sufficiently dry to 

 work in the ordinary way. This made planting so late that the crop was 

 a failure, while a heavy crop was secured on the land disked while wet. 



Professor King, in his book. "The Soil." says that it requires nine 

 and two thirds times as much heat to evaporate water from the soil as it 

 does to warm an equal quantity of water in the soil 100 degrees. Does 

 not this explain why Mr. Hunt and the writer found disking so effective 

 In warming the soil? The disking made a good surface mulch that pre- 

 vented evaporation of water from the soil and the consequent cooling f 

 it, and turned the full effect of the sun's heat into warming the land. 



This spring the soil is unusually wet and cold on many farms, and 

 our experience shows that on such land a thorough disking will hasten 

 the warming of the soil sufficiently to allow of at least a week's earlier 

 planting than on untouched soil. 



Sac county, Iowa. 



THE BY-PRODUCTS OF CORN. 



Wallace's Farmer'. 



For the sake of our thousands of new subscribers it may be worth 

 while to mention a great number of by-products of corn which have 

 been constantly increasing, and will increase from year to year, thus 

 giving new value to the corn crop, from which, directly or indirectly, 

 western farmers receive most of their profit. 



When corn is taken to the glucose factory, for example, it is first 

 s'oaked in water for from thirty to forty hours. It is then passed 

 through mills freely supplied with water, which remove the hull, free 

 the germ, and break up the starch. Scarcely any of our readers need 

 to he told that the four principal ingredients of corn are the hull, or 

 bran; the germ; the dark looking substance in the center and on the 

 top, mostly starch; and the hard substance on either side, which con- 

 tains much gluten, but more or less starch. This pasty mass is run 

 through a large trough of running water, which floats off the germ, the 



