PLOUGHING AND DRAINING. 141 



has a further value than has yet been suggested : ' Rain water 

 always contains in solution air, carbonic acid, and ammonia ; 

 the two first are among the most powerful disintegrators of the 

 soil ; the oxygen and carbonic acid being both in a highly 

 condensed form by being dissolved, possess very powerful 

 affinities for the ingredients of the soil ; the oxygen attacks and 

 oxidizes the iron," the carbonic acid seizing the lime and potash 

 and other alkaline ingredients of the soil, produces a further 

 separation and renders available the locked up ingredients of 

 this magazine of nutriment ; before these can be used by plants 

 they must be rendered soluble, and this is only effected by the 

 free and renewed access of rain and air. The ready passage of 

 both of thesef therefore, enables the soil to yield up its latent 

 nutriment.' 



" Hence, we see that the rains of heaven bring us not only 

 water, but food for our plants, and that, while we would remove 

 by proper drainage, the surplus moisture, we should take care 

 first to conduct it through the soil far enough to fulfil its 

 mission of fertility. We cannot suppose that rain water brings 

 to our fields precisely the same proportion of the elements of 

 fertility, because the foreign properties with which it is charged 

 must continually vary with the condition of the atmosphere 

 through which it falls, whether it be a thick and murky cloud 

 which overhangs the coal-burning city, or the transparent ether 

 of the mountain tops." 



Now the question arises. What lands need drainage ? 

 Evidently those lands that retain the surface water until late in 

 spring or early summer, so that teams cannot work upon them 

 to good advantage, require at least, superficial drainage ; it is 

 frequently necessary as well as convenient, to be able to culti- 

 vate a field a week or ten days earlier ; by so doing the extra 

 crop in one season would, in many cases, pay the expense ; 

 fields that are known to grow willows, rushes and alders indicate 

 deep drainage, as these aquatic plants would not grow and 

 flourish were it not for the water in the subsoil that encourages 

 their growth ; again, where trees or grain leave badly in 

 spring, or when the foliage presents a sickly appearance, it is a 

 strong index of stagnant water in the subsoil. 



A member of this Committee having decided to transplant a 

 pear orchard at some future day, and having learned that the 



