The Science of the Soil 



IOI 



weather the fine particles of dust and grit are borne from one place to 

 another, together with leaves, twigs, and other organic material. Fresh 

 surfaces are thus laid bare again for the action of rain, frost, snow, &c. 

 Vegetation. It is thought that in the early stages of the earth's career 

 only the lower forms of vegetable life could find a footing on its surface. 

 The various Algae, Lichens, Mosses, were able to pick up a living at first. 

 In due course they died, and their remains mingled with the surface soil, 

 thus gradually bringing about a compost suitable for the growth of higher 



plants 



" Dissolve to dust and make a way 

 For bolder foliage nursed by their decay ". 



And so on, from one stage to another, one class of plants succeeding 

 another, and some even being crushed out of existence altogether, as we 

 learn from the fossil remains found in coal seams, shale, &c. 



Animals, when they came, helped also to make our soils, and, like the 

 primitive plants, many of these died out under the stress of competition 

 from newer races. Worms also play an important part in the ventilation 

 of the soil, and wherever very large numbers are present it may be taken 

 as a sign that the subsoil is in a wet and heavy condition, and should be 

 trenched or at least double dug. 



These natural soil-forming agencies, although of the greatest importance, 

 are nevertheless too slow for horticultural and agricultural purposes. If 

 a farmer or a gardener waited until the rain, frost, snow, heat, cold, and 

 wind, fec., converted a heavy clay soil into a fertile condition, he and his 

 race would soon become extinct. He therefore hastens the process of dis- 

 integrating various rocks and soils by such cultural operations as ploughing, 

 digging, trenching, manuring, &c. He " tills " the ground, and by ever 

 exposing fresh surfaces to the natural agencies of the weather, he, more 

 or less quickly, brings the soil into a condition capable of bearing large 

 crops of cereals, fruits, flowers, and vegetables. This condition is known 

 as fertile, whereas a soil that will not respond to such operations is known 

 as sterile. 



5. CULTURAL OPERATIONS 



Ploughing*. Although regarded as being almost entirely an agricul- 

 tural operation, many market gardeners also adopt this method of breaking 

 up their open land, and often even use the plough between fruit trees and 

 bushes when space permits. 



Ploughing itself requires a good deal of skill on the part of the work- 

 man. A good ploughman will not only adjust the implement in such a way 

 as to place as little strain as possible upon his horses, but he will also per- 

 form more good work in a given time than an unskilled or slovenly worker. 



In ploughing, the surface soil only is broken up to a depth of 6 in. or 

 8 in., the width of each furrow being about 10 in. on an average. The cost 

 of ploughing an acre of ground is about 15s., but it may be more or 



