28 MANURES. 



the name of Gcine. When wet, it is a gelatinous mass, which, on drying, be- 

 comes of a deep brown, or almost black colour, without taste or smell, and 

 insoluble in water; and therefore, in this state, incapable of being absorbed by 

 the roots of plants. Yet, after the action of alkalies upon it, it assumes the cha- 

 racter of an acid, and unites with ammonia, potassa, lime, alumina, &c., and 

 forms a class of bodies called Geates, most of which are soluble in water^ and 

 therefore capable of being taken up by plants. And it is in this state of geates, 

 that this substance for the most part exists in the soil. Economical Geograph. 

 of Massachusetts , by Edward Hitchcock, Esq. 



The statements of BERZELIUS, though highly interesting in 

 a theoretical point of view, afford very little light, and conse- 

 quently but little information to the practical agriculturist. 

 Those of Dr. SAMUEL J. DANA appear far more important, in 

 a scientific as well as a practical view of the subject, notwith- 

 standing they essentially coincide with those European che- 

 mists as far as they have gone.* "This method of analysis, 

 derived from his researches, I must say, after having made 

 extensive application of it to our soils, is simple and elegant 

 and, taken in connexion with his preliminary remarks it ap- 

 pears to me to be a most important contribution to agricultural 

 chemistry, and promises much for the advancement of practical 

 agriculture."! 



By Gcine, says Dr. Dana, I mean all the decomposed organic matter of the 

 soil. It results chiefly from vegetable decomposition animal substances pro- 

 duce a similar compound containing azote. Geine exists in two states soluble 

 and insoluble: soluble both in water arid in alkali in alchohol and acids. So- 

 luble geine is the food of plants. Insoluble geine becomes food by air and 

 moisture. Hence the reason and result of tillage. Hence the reason of em- 

 ploying pearl ash to separate soluble and insoluble geine in analysis. These 

 are the facts. Will they not [ultimately] lead us to a rational account of the 

 use of lime, clay, ashes and spent ley? Will they not account for the supe- 

 riority of unferrnented over fermented dung in some cases? 



Gcine forms the basis of all the nourishing part of all vegetable manures. 

 The relations of soils to heat and moisture depend chiefly on geine. It is in 

 fact, under its three states of "vegetable extract, geine and carbonaceous mould " 

 the principle which gives fertility to soils, long after the action of common, 

 manures has ceased. In these three states it is essentially the same. The ex- 

 periments of SAUSSURE have long ago proved that air and moisture convert 

 insoluble into soluble geine. Of all the problems to be solved in agricultural 

 chemistry, none is of such great practical importance as the determination of 

 the quantity of soluble or insoluble geine in soils. This is a question of much 

 higher importance than the nature and proportions of the earthy constituents, 

 and soluble salts of soils. It lies at the foundation of all successful cultivation. 

 It.s importance has been not so much overlooked as undervalued. 



Among the few facts best established in chemical agricul- 

 ture, are these: That a soil, whose earthy part is composed 

 wholly, or chiefly, of one earth; or any soil with excess of 

 salts, is always barren; and that plants grow equally well on 

 all soils, destitute of geine, up to the period of fructification 



* It is but justice to say, that Dr. Dana derived his knowledge of geine chiefly 

 from his own researches, made with a view to improve the colouring process 

 in the calico printing establishment at Lowell and his method of analyzing 

 soils is altogether original. Hitchcock's Geology.' t Ibid., page 30. 



