14 AMERICAN AGRICULTURE. 



"To 100 grs. of the dry soil diffused through half a pint of 

 cold water, *add half a wine glass-full of muriatic acid (the 

 spirit of salt of the shops), stir it occasionally during the day, 

 and let it stand over night to settle. Pour off the clear 

 liquor in the morning and fill up the vessel with water, to 

 wash away the excess of acid. When the water is again 

 clear, pour it off, dry the soil and weigh it the loss will 

 amount generally to about one per cent, more than the quan- 

 tity of lime present. The result will be sufficiently near, 

 however, for the purposes of classification. If the loss 

 exceed 5 grs. from 100 of the dry soil, it may be classed 

 among the marls, if more than 20 grs. among the calcareous 

 soils. 



" Lastly, vegetable matter is sometimes the characteristic 

 of a soil, which gives rise to a further division of 



" 9. Vegetable moulds, which arc of various kinds, from the 

 garden mould, which contains from 5 to 10 per cent., to the 

 peaty soil, in which the organic matter may amount to 60 or 

 70. These soils also are clayey, loamy, or sandy, according 

 to the predominant character of the earthy admixtures. 



" The method of determining the amount of vegetable 

 matter for the purposes of classification, is to dry the soil well 

 in an oven, and weigh it ; then to heat it to dull redness over 

 a lamp or a bright fire till the combustible matter is burned 

 away. The loss on again weighing is the quantity of organic 

 matter." 



The foregoing are only such general divisions as possess 

 properties sufficiently common to each, to require a treatment 

 nearly similar. Besides their principal component parts, 

 every soil must contain in greater or less quantities, all the 

 elements which enter into the composition of vegetables. 

 They may have certain substances which are not necessary 

 to vegetable life, and some one or all of such as are, may be 

 contained in excess; yet to sustain a healthy prolific vegeta- 

 tion, they must hold, and in a form fitted to its support, silex 

 alumina, carbonate of lime, sulphate of lime, potash, soda, 

 magnesia, sulphur, phosphorus, oxide of iron, manganese, 

 chlorine, and probably iodine. These are called the inorganic, 

 or earthy parts of soils, ;s they arc found almost ex- 

 clusively in combination with rurlhs, salts, or minerals. 

 They however constitute from less than 0.5 (one half of one) 

 to over 10 per cent of all vegetables. In addition to these, 

 fertile soils must also contain, carbon, oxygen, nitrogen and 

 hydrogen, which are called the organic parts of soils, froniv 



