296 



Journal of Agriculture, Victoria. [10 Mat, 1917. 



An increase in the pounds of phosphoric acid forms other than water 

 soluble received is shown during the years 1907-13, but the years 1915-17 

 show a noted decline until the 1907 figure of 8.5 lbs. is decreased to 

 4.6 Ib^. 



The following table will probably illustrate more clearly: — 



The Purchase of Superphosphate. 



Year. 



Amount 

 expended. 



Water solubles, 

 phosphoric acid 



Weight in pounds received. 



Phosphoric 



acid in other 



forms. 



Percentage 



decrease. 



water soluble 



phosphoric 



acid. 



Percentage 



decrease. 



phosphoric 



acid in other 



forms. 



Percentage 



increase, 



phosphoric 



acid in other 



forms. 



1907 

 1913 

 1917 



20/- 

 20/- 

 20/- 



Ibs. 



103-5 



87-0 



79-0 



lbs. 



8-5 



14-0 



4-0 



/o 



le" 



9-2 



0/ 



/o 

 67-1 



/o 

 64-7 



A reference to Graph No. I., which appears on page 297, will give 

 additional particulars in regard lo the purchase of superphosphate 

 during the years 1912-17. 



The pillar column on the extreme left of the graph depicts the 

 number of pounds of phosphoric acid in the three forms received in 

 return for 20s. expended in the purchase of "super" during the period 

 under review. 



The numerals at the foot of the pillar column denote the year, the 

 unshaded portion serves to illustrate the pounds of water soluble phos- 

 phoric acid received, whilst the one-way shading denotes pounds of 

 citrate soluble phosphoric acid, and the cross shading the pounds of 

 citrate insoluble phosphoric acid. 



It will be noted that the year 1916 shows a fall in the grade of the 

 fertilizer, and the year 1917 shows both a fall in grade and an increase 

 in price. 



Sodium Nitrate. 



The most readily available form in which the essential plant food 

 nitrogen may be purchased is in the form of nitrate as sodium nitrate — 

 more commonly known as nitrate of soda — a term which is not strictly 

 correct. 



This fertilizer is imported from abroad, viz., from Chili, and 

 naturally one would expect war increase in the price of sodium nitrate. 



A reference to the second diagram on Graph I. appended will dis- 

 close the number of pounds of nitrogen received in exchange for every 

 20s. spent by the farmer in the ])urchase of sodium nitrate during the 

 past six years. 



The vertically shaded pillai's denote the number of pcn^I' of nitro- 

 gen, the figures giving the number nf pound"? received in the various 

 years which are set out at the foot of each pillar. 



The grade of this fertilizer shows no variation, but the price has 

 risen. In 1912 sodium nitrate could be purchased at £13 10s. per 

 ton. In 1913 a rise took place, the average price being £14 9s. per 

 ton. This price held within Is. during the years 1913, 1914, 1915, 



