194 MANURES. [Vm. 



5. The progress of growth varies according as the feldspar 

 is used in the state of coarse or fine powder. 



6. Manure exerts its fertilizing action also at a distance. 

 It then acts, not only by conveying certain mineral matters 

 to the soil, but its organic constituents also contribute, and 

 that essentially, to the promotion of vegetation. 



For a more detailed account of Magnus's experiments, see 

 Chem. Gaz. viii. 261. 



Common Salt. — The injurious effects of common salt on 

 vegetation were clearly shown in a case reported to the British 

 Association. See Amer. Journ. 2d ser. vii. 299. 



W. B. Randall (Ch. Gaz. vi.) has proved by experiment 

 that water, containing as much as seven grains of chloride of 

 sodium to the pint, is highly destructive to the weaker forms 

 of vegetation. 



On the other hand, Dubreuil, Fauchet, and Girardin ex- 

 perimented practically on the effects of common salt on wheat, 

 and found that in the ratio of 6-8 |ft) per acre, the straw and 

 grain were both heavier ; when more salt was employed, the 

 straw was more influenced than the grain. 



Persoz found that hortensias flourished far more in an or- 

 dinary soil manured, than the same not manured ; the manure 

 being 61]b boneblack, SSb nitric acid, and lib phosphate of 

 potassa. A vine manured with life silicate of potassa, SSb 

 phosphate of potassa and lime, and an equal weight of dried 

 blood and goose-dung, produced a shoot of more than 11 yds. 

 in a year, while another, not manured, gave a shoot of only 

 4| yds. ; the former produced on nine shoots 25 bunches of 

 .grapes, the latter none. 



Polstorff (Ann. Ch. Pharm. Ixii. 192) drew the following 

 conclusions from experiments with salts upon barley grown in 

 lead-lined boxes, and in the field : 1. That barley reaches its 

 full development in a soil containing only the constituents of 

 its ashes ; 2. That the amount of nitrogen in grain is therefore 

 not dependent on the soil ; 3. That mineral manures are ca- 

 pable of producing entirely different results, according to the 



