834 



ANNUAL REPORT OF THE 



Off. Do«. 



TABLE 8. 

 Slag phosphate Produced. 



Year. 



Tons. 



1878, 

 1879, 

 18S0, 

 1881, 

 1882, 

 1883, 

 1884, 

 1885, 

 1886, 

 1887, 

 1888, 

 1889, 

 1890, 

 1891, 

 1892, 

 1893, 

 1894, 

 1895, 

 1896, 

 1S97, 

 1898, 

 1899, 

 1900, 

 1901, 



4 



MO 



16,000 



100,000 



135.000 



190, *U 



259.000 



283,495 



412. »03 



511. U4 



685.970 



682. S«o 



783. »:4 



720,134 



800,660 



874.000 



896,301 



934,235 



962. OoO 



1,033.002 



1, 105, 000 



1,250,120 



1.462,325 



1,700,000 



BASIC SUPER-PHOSPHATE. 



This is a class of super-phosphate that was introduced in the Eng- 

 lish market in 1900. It is made up of a mixture of slaked lime and 

 ordinary super-phosphate. The idea that led up to the making of 

 this mixture was caused by an effort to produce an alkaline phos- 

 phate with some of the characteristics of slag phosphate, but one 

 which would also give results on sandy and other soils that were 

 deficient in organic matter. This basic super-phosphate can also 

 be used on soils which are acid and upon which ordinary super- 

 phosphate (acid phosphate) gives poor results. In fact, the claim 

 is made for it that it possesses all the advantages of both slag phos- 

 phate and of acid phosphate. 



The following laboratory experiments* show the relative solubilii/ 

 of basic slag phosphate and the basic super-jjhosphate: 



♦Experiments of John Hughes, originator of the ba^ic super-phosphate. 



