558 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



ers turn out from 1000 to 20,000 tons each per annum. An 

 idea of the magnitude of the manufacture of, and trade in, 

 artificial manures in England can be formed from the fact 

 that the importations into England of phosphatic minerals, 

 bone-ash, and phosphatic guano, from all parts of the world, 

 for use as raw materials for the manufacture of artificial ma- 

 nures, probably exceed 500,000 tons per annum." 



Fertilizers for Root Crops. 



"By far the largest quantity of all manufactured manures 

 is used in England for root crops. There are many parts of 

 England where turnips and swedes are grown with no other 

 manure than mineral superphosphate, containing on an aver- 

 age 21 to 25 per cent, of soluble phosphate of lime [ = 9|- to 

 11-j per cent, of soluble phosphoric acid], at the rate of three 

 to four hundred-weight per acre. On cold, clay soils, in a fair 

 agricultural condition, it has been found that three hundred- 

 weight of such a mineral superphosphate Avill produce at 

 least as heavy a crop of swedes and turnips as a manure con- 

 taining, in addition to soluble phosphate of lime, ammonia or 

 nitrogenous matter. On light land, however, the use of pure- 

 ly phosphatic manure cannot be relied upon for producing a 

 good crop of roots. On such land artificial manures are sel- 

 dom used alone, but usually in conjunction with half a dress- 

 ing of common dung. Dissolved bones, Peruvian guano, or 

 compound artificial manures, containing from 2 to 3 per cent. 

 of ammonia, are greatly preferred to mineral superphosphate 

 as a manure for root crops on light land and on loamy soils 

 out of condition. 



"Nitrate of soda lias also been used of late years in Eng- 

 land with considerable advantage, in addition to dissolved 

 bones, or a mixture of superphosphate and guano, and some 

 salt, as a manure for mangolds. A dressing of one and a half 

 hundred-weight of nitrate of sodn, three hundred-weight of 

 Peruvian guano, two hundred-weight of superphosphate, and 

 two hundred -weight of salt per acre is considered a some- 

 what heavy but well-paying manure for mangel-wurzel." 



Fertilizers for Grain Crops. Guano and Nitrate of Soda. 



"Both raw and dissolved Peruvian guano are largely used 

 by the farmers of Great Britain. Of late the consumption 



