1897.] PUBLIC DOCUMENT — No. 33. 210 



pable powder, which cannot fail to increase the availability 

 of its phosphoric acid in a marked degree, as compared with 

 other non-acidulated ground phosphates. 



Not less beneficial must be considered in many instances 

 the alkaline reaction of the genuine material, for it secures 

 favorable conditions not only for a rapid decomposition 

 ("nitrification") of the organic matter of the soil, but also 

 for the disintegration of v^aluable mineral constituents of the 

 soil, rendering in both directions inherent plant food more 

 available. Much attention has been paid in Germany and 

 England to experiments with slag meal as a phosphoric acid 

 source of plant food, and many satisfactory results are re- 

 ported. Our own observations are, to say the least, very 

 encouraging, as may be seen from several annual reports 

 since 1887. 



Mixtures of phosphatic slag with nitrate of soda and the 

 higher grades of potash salts have given in many instances 

 much satisfaction. To secure the full benefit of the action 

 of slag meal, it is desirable to scatter it broadcast late in the 

 fall or early in the spring, and to plough it under at once 

 from three to four inches ; nitrate of soda and potash salts 

 may be harrowed in later on, previous to seeding down. 



The high price (from $20 to $25 per ton) of late charged 

 for phosphatic slag meal of a varying composition and gen- 

 eral character has discouraged its trial, as compared with the 

 ground phosphate of South Carolina and Florida. As the 

 high price has greatly interfered with a more general trial of 

 slao; meal, it is of interest to learn that arrano-ements are 

 announced which will result in introducing large supplies of 

 it at a much lower cost than ])efore. A German syndicate, 

 claiming to own the right of })atent regarding the sale of 

 Thomas slag in Europe and the United States, has estab- 

 lished an office in Philadelpliia, Penn., address Charles A. 

 Voight, P. O. box 2133, Station A. In a recent communi- 

 cation fi'om him it is stated the article will be oft'ered for sale 

 at from $8 to $9 per ton to farmers in the eastern States. 

 The material consists of a dark, fine powder ; it is sent out 

 in 200 pound i)ags, with a guarantee of 18 per cent, of phos- 

 plioric acid. The station has secured a quantity for trial 

 durino; the comino' season. 



