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monstrated that intense sunlight destroys those harmful soil or- 

 ganisms vv'hich prey on the plant-food making bacteria. The 

 illuminating researches of these scientists enable us more readily 

 to understand the spontaneous and marvellous fertility of the 

 lands of South Africa which are bathed in sunshine. 



The germ of life of arid lands is a subject worthy of the atten- 

 tion of the Universities of the Empire. 



The well-known term soil-mulch is deserving of a brief notice. 

 It may be defined as "any material which is spread upon the soil 

 to shade the surface from the sun and to break the connection 

 between the water-bearing sub-soil and the exposed surface." 

 Examples of mulching are familiar to everyone. Turn over a 

 board or stone lying on the ground, and you will find that the soil 

 beneath is moister than the ground around it, since the pores of 

 the earth, or capillary channels, have been closed, and the current 

 of moisture passing upward to the surface has been stopped. In 

 the garden, leaves, straw, and manure are commonly used. But 

 the most practical mulch is made of loose, dry soil. This is done 

 by frequently stirring the surface of the plowed lands with a 

 harrow or cultivator. The soil-mulch is also termed the soil- 

 blanket. 



Now the question arises: "How deep should the soil-blanket 

 be ?" The reply is : From two to six inches, depending on the 

 state of the weather, the soil, and the crop. In orchard cultiva- 

 tion, during a severe drought, the soil-blanket is often made six, 

 inches deep, or even more. But for cereals the soil-blanket should 

 seldom be thicker than two to three inches, as they are surface 

 feeders. \V'hen sowing, the seed must be drilled into the moist 

 seed-bed below the dry blanket, otherwise it may fail to ger- 

 minate. 



SUMMARY OF RESULTS. 



It is doubtful if, since the time of Tull, any soil has had a 

 severer test of his profound but forgotten principles than the dry 

 lands of Lichtenburg in the Western Transvaal. Let us sum- 

 marize what has been accomplished there. 



We have shown : 



(1) That by our system of tillage we are able to keep the 

 soil seed-bed moist for a whole year. This means that, so far 

 as moisture is concerned, we can plant a crop at any season — a 

 most important matter in South Africa. This result has been 

 attained by the use of moisture-saving fallows, deeply plowed, 

 constantly harrowed, and kept covered with a dry-soil blanket 

 which checks evaporation. 



(2) That it is possible to grow dry land winter wheat and to 

 harvest it before the season of rust. 



(3) That drilling, as might be expected, is far better than 

 broad-casting, saves seed, places the grain in the moist seed-bed, 

 and "fives a more even growth. 



