TRUCK-FARMING AT THE SOUTH. 



containing ammonia, 7.12 Ibs. 



By reducing the analyses to weights and measures it is 

 found that 



ONE TON OF FRESH COW PEA VINES CONTAIN 



Water 1456.30 Ibs. 



Potash 5.93 



Soda 9.33 



Magnesia 3.70 



Lime 9.03 



Phosphoric acid 3.73 



Sulphuric acid 0.94 



Silica 0.43 



Chlorine 0.08 



Carbonic acid 7.88 



Albuminoids 37.00 



Cellulose 305.40 



Fat 4.30 



Carbohydrates 156.30 



3000.00 Ibs. 



Boussingault found that snow, which had lain for 

 thirty-six hours on the soil of a garden, contained ten 

 times as much ammonia as the snow of the same fall 

 from a contiguous stone terrace immediately after falling, 

 the mulch of snow having interrupted the ammoniacal 

 emanations from the soil. The ammonia of the soil is 

 constantly undergoing change, and fluctuating in quantity. 

 This most important article of plant food, and most ex- 

 pensive, when applied artificially, is most abundantly ab- 

 sorbed by the soil in summer from the atmosphere, and 

 being conveyed to it by rains and dews, and continually 

 being taken up by vegetation, it is volatilized, evaporated 

 with water, washed away and lost. Later and more 

 exact chemical experiments have shown that the soil 

 contains less ready-formed ammonia than was formerly 



held to be the Case. Ammonia in dry soil. 



Very light sandy soil from birch forest 0.00077 per cent. 



Rich lime soil from beech forest 0.00087 



Sandy loam, forest soil 0.00013 



Forest soil 0.00080 



Meadow soil, red sandy loam 0.00027 



Average 0.00056 



It should be remembered that ammonia is only half as 

 heavy as air. 



