1847.] Mi7ieral Food for Plants in the Soil. 53 



water only, the former for three, and the latter for eight years, 

 give a different complexion to the matter, for they were barely 

 kept alive, growing but very little. It was evident therefore that 

 they did not derive much sustenance from the water. 



Of a similar kind was Jethro Hull's theory, that if the soil 

 were finely divided, plants would thrive in it without manure. In 

 the same class of theories, may be ranked that which makes the 

 atmosphere the great storehouse of vegetable food, and which 

 would make it unnecessary to apply any manure to the soil; a 

 theory utterly inconsistent with all experience, and along side of 

 it we must place the doctrine of soaking seeds in saline solutions, 

 to impregnate them with a sufficient quantity to sustain a growth 

 of increased vigor, and an Increased production of fruit. 



All these theories, and the multitude of others which would 

 make it unnecessary to manure the ground, must rest side by side. 

 They will not be confirmed by practice. Plants must be fed. 

 They must have all the elements necessary to make them perfect. 

 Water alone is not sufficient — any single salt, or mixture of salts, 

 will not be the thing unless it contain all the plant requires, and 

 in such a form that the plant can obtain it. The earth was made 

 for them to grow in, and was formed and mixed by the Creator 

 in the wisest and best manner possible. If He has left us any 

 thing to add, then let us find it out. He certainly did not leave 

 us to discover that plants will grow in the air, or in the water 

 better than in their natural soil. 



From the known constitution of plants, we should have no 

 hesitation in infering that they require food. Experience teaches 

 us that it is the case. Unraanured soil will not produce good 

 crops. A succession of crops taken off the same land, impover- 

 ishes it, unless some of the loss is restored. If weight is restored, 

 equal to what is taken off, in the ordinary form of manures, that 

 is, in the form of dwwg, vegetable or animal matter; we still find, 

 in the process of time, a deterioration in the capabilities of the 

 soil, manifested in its diminished and constantly diminishing pro- 

 ductions. To this cause is owing the " wearing out," as it is 

 called, of old cultivated lands, even under what may be considered 

 a liberal system of husbandry. These facts teach us that some- 

 thing is required for the sustenance of the plants we wish to grow. 

 What is this? 



The substances entering into the constitution of vegetables, 

 have, as it appears to us without much reason, been divided into 

 two classes, according to their origin, or perhaps rather in accord- 

 ance with an opinion no longer held by any, that only four, of all 

 the elements found in plants, belonged essentially, the others 

 being present only by accident. These four were called organic 

 — the rest inorganic. From the circumstance that upon the death 



