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Basic slag is specially suited to clay, peat and sandy soils, also 

 moor-land and wet meadows. Maercker has found that for barley, 

 potatoes, oats and sugar beets on moor-hnd soil, basic slag is better 

 than superphosphates and precipitated phosphates. He recom- 

 mends when sown in the spring 2 cwt. of basic slag and i cwt. of 

 superphosphates as being the most profitable. They can be mixed 

 and sown with potash and nitrate of soda. The mixture should be 

 made just before sowing, as if it is allowed to stand for a week or 

 two it sets. It cannot be sown or mixed* with sulphate of ammonia, 

 as it contains free lime, and would cause a loss of ammonia. The 

 ammonia must be applied some time after the slag. It will be found 

 very advantageous to sour land by neutralizing the acidity, 

 as well as acting as a manure. The phosphoric acicl in basic slag has 

 only half the effect that the phosphoric acid in superphosphate has ; 

 that is, 100 Ibs. of phosphoric acid in superphosphates will have 

 the same effect as 200 Ibs. of that in basic slag will have. The 

 results of the following experiments by Wagner will show this, and 

 also the difference between basic slag and superphosphates and 

 Peruvian guano, bone-meal, and ground coprolites on the same 

 crops. Nitrogen and potash were added to the superphosphates, 

 slag, bone-meal, and coprolites, so as to make them equal in other 

 respects to the Peruvian guano, and so that the test should be con- 

 fined to the phosphoric acid. The crops experimented on were 

 barley, wheat, and Hax. The amount of crops obtained by the use 

 of superphosphate \Va- T ,ner called 100, the other amount of crops 

 by the different manure shows the percentages, as compared with 

 superphosphates, as 100. This will give the manunal values of the 

 other phosphates : 



As basic slag generally contains about So per cent, of line and 

 20 per cent, of coarse phosphates, its value compared with super- 

 phosphates will be 50 or one-half, that of Peruvian guano one-third, 



