276 HANDY-BOOK OP HUSBANDRY. 



" the acid ■■, while in the case of certain plants only a third, or 

 *' even less of the residue is taken up by the acid. 



" The parts of the ashes soluble in cold water consist entirely 

 " of salts with alkaline hases^ {^potash and soda.) The ingredients 

 " soluble in acids are salts of lime and magnesia ; and the residue 

 " insoluble in acids consists of silica. 



" These ingredients being so different in their behavior to water 

 " and to acids, afford us a means of classifying the cultivated plants 

 " according to their unequal quantity of these constituents. Thus 

 '' potash plants are those the ashes of which contain more than half 

 " their weight of soluble alkaline salts ; we may designate as li/ne 

 " plants and as silica plants those in which lime and silica respect- 

 '' ively predominate. The ingredients thus indicated are those 

 " which form the distinguishing characteristics of the plants which 

 " require an abundant supply of them for their growth. 



" The potash plants include the chenopodia, arrach, wormwood, 

 " etc. ; and among cultivated plants, the beet, mangel-wurzel, 

 ^' turnip, and maize. The lime plants comprehend the lichens, 

 " (containing oxalate of lime,) the cactus, (containing crystallized 

 *' tartrate of lime,) clover, beans, peas, and tobacco. Silica plants 

 " include wheat, oats, rye, and barley. 



Salts of Salts of 



Pot-ish and Lime and Silica. 



Soda. Magnesia. 



r Oat straw with seeds 3400 400 62*00 



I Wheat straw 2200 7-20 61 OC 



Silica Plants. <„,,.,, ^ 



j Barley straw with seeds 1900 -57° SS'Oj 



(^ Rye straw 18-65 16-52 63-89 



r Tobacco (Havana) 24-34 67-44 8-30 



I " (Dutch) 23-07 62-23 ^S'-S 



" (grown in an artificial soil) 2900 59-00 12-00 

 Lime Plants, -'do. or 



■j Pea Straw 2782 6374 7-81 



Potato herb 4-20 59'+o 36*40 



l^ Meadow clover 39-20 56-00 4-90 



Maize straw 71-00 6-50 iS'OO 



Turnips 81 60 18-40 



Potash Plants. -^ Beet-root 88-00 12-00 



Potatoes (tubers) 85-81 ^4-'^9 



[^ Helianthus tuberosus 84-30 157° 



