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TRANSACTIONS OF THE 



the disintegration of felspars. The red clays of New Jersey contain 

 protoxide of iron, and are great absorlients of oxygen ; they do not become 

 fertile until the protoxide is converted into peroxide. Soils thus being 

 formed for the reception of seeds by the disintegration of rocks, their pro- 

 perties are dependent upon the component parts of the rocks, and the 

 effects produced upon them by the action of the water and air to which 

 they are exposed. The constituents of these soils, are clay, lime and 

 sand ; the first, being produced by the disintegration of mica, felspar, and 

 other aluminous minerals, possess the fructifying element of all soils ; the 

 sand contains no inorganic substance, except carbonate and silicate of lime, 

 and consequently afford no nourishment for vegetation. The lime acts with 

 great efficacy upon land containing vegetable or animal substances, and 

 frequently produces more durable and nourishing effects, than the applica- 

 tion of barnyard manure, because it renders every particle of them useful 

 to the preparation of the soil, and germination of the seed. Of saline 

 substances used as a preparation of the soil for the reception of seed, chlo- 

 ride of sodium has received the most attention, and has been extensively 

 applied, but I am opposed to its use in large cjuantities, from the fact that 

 the shores of the ocean are generally sterile. There is great diversity of 

 opinion among agriculturists as to its value as a manure, and no data has 

 been given regarding the quantity to be applied, or the proper season for 

 applying it. My experiments lead me to believe that six bushels to the 

 acre should never be exceeded. Saltpetre has been effectually tried as a 

 manure, but, being expensive, experiments are required to confirm its 

 value. 



The whole subject of the germination of seed, and the fitness of soil for 

 its reception, is one of engrossing interest to the agriculturist, and deeply 

 interesting to the physiologist, who can make but little proficiency in the 

 study without investigating the means by which plants derive their nourish- 

 ments from the soil, and how they are admitted into the interior of them. 

 We find by examination, that essentially a plant consists of three parts — 

 roots, stems, and leaves. The former push themselves great distances, in 

 every imaginable direction, through the earth, to obtain food, in order to 

 increase the stem and leaves, which make a corresponding advancement 

 through the atmosphere, and increase their leaves and luxuriance in pro- 

 portion to the extension of the roots. 



The stems of plants consist of the pith, wood, bark, and medullary rajs. 

 The pith and rays are extensions of the same substance. The pith forms 

 the centre of the stem, the wood encircles it, and the bark completes the 

 cylinder. The stem is fitted with capillary tubes of various sizes, through 

 which the llf|uid and gaseous substances are conveyed to the branches. 

 The roots and branches of a tree are capable of being reversed, and made 

 to bear on their changed prolongations. I once, by degrees, reversed a 

 currant bush, and in due course of time, the roots became branches, and 

 bore fruit, while the branches became roots, and sustained them. The 

 banana tree is a familiar example of this convertible power contained iu 



