19 



to branch out numerous others, by which the mouths or pores 

 of the plant are greatly increased, and such food as is in the soil 

 has the better chance of being sought after and taken up by them . 



Pulverization increases the capillary attraction, or sponge-like 

 property of soils, by which their humidity is rendered more uni- 

 form. It is proved that capillary attraction must be greatest 

 when the particles of the earfch are finely divided, for gravel and 

 sand hardly retain water at all, while clays not open by pulveriza- 

 tion, or other means, either do not absorb water, or when by 

 long action it is absorbed, they retain too much. Water is not 

 only necessary to the growth of plants, as such, but it is essential 

 to the production of extract from the vegetable matters they 

 contain, and unless the soil, by pulverization or otherwise, is so 

 constituted as to retain the quantity of water requisite to produce 

 this extract, the addition of manures will be in vain. Manure is 

 useless to vegetation until it becomes soluble in water, and it 

 would remain useless in a state of solution if it so abounded as 

 wholly to seclude air, for then the fibres or mouths, unable to 

 perform their functions, would soon decay and rot off ; as is the 

 case with flowers or shrubs in pots where there is no opening, so 

 that the air cannot circulate round the roots. 



Pulverization leads to the increase of vegetable food. Water is 

 known to be a condenser and solvent of carbonic acid gas ; which, 

 where the land is open, can be immediately carried to the roots 

 of vegetables, and contributes to their growth ; but if the earth 

 be close, and the water lie on or near its surface, then the car- 

 bonic gas, which always exists in the atmosphere, and is carried 

 down by rains, will soon be dissipated. An open soil, therefore, 

 is always suitable for effecting those changes in the manure itself 

 which are equally necessary to the preparation of such food. 

 Animal and vegetable substances exposed to the alternate action 

 of heat, moisture, light and air, undergo spontaneous decom- 

 position which would not otherwise take place. A very good 

 compost for improving stiff soils is made by equal parts of lime 

 and woodashes with two parts of sand. 



In soils that are very light, it is advantageous to roll or beat 

 down seeds, as it prevents the light soil from drifting, and also 

 (a very material point) hinders ants from carrying them away. 



