206 
of nitrogen derived from blood, bones, or meat would produce an 
increase of 700lbs., and a similar dressing of nitrogen from wool 
waste, hair, ground horn, or leather would only produce an increase 
of 200 to 300lbs. of fruit. It is thus seen how important in select- 
ing the materials from which nitrogen, phosphoric acid, and potash 
are to be derived to see that the material is readily available. 
Phosphorie acid varies greatly’ in value, whether it is soluble 
or insoluble in water. As regards “Citrate soluble’? phosphoric 
acid—i.e., from a phosphate soluble in a weak acid solution, such 
as one of ammonium citrate—the value is intermediate between 
the above two, thus: Water soluble phosphorie acid is worth in 
Western Australia 7s. Phosphoric acid insoluble in water is worth 
with us 3s. a unit, whilst citrate soluble phosphorie acid is worth 
here 5s. 
Potash in soluble salts is worth in Western Australia 6s. to 
7s.; while potash in natural manures, such as dried nightsoil, is 
worth 5s. and 4s. respectively. These prices, of course, fluctuate 
a little according to the state of the market, the quantity of 
fertilisers bought, and as to whether the transaction is a cash one 
or one involving terms. 
The state of subdivision in which some fertilisers occur is 
hardly ever given in the analysis, yet this is a most important 
factor of the manure’s worth. 
‘To arrive at the value of a fertiliser, and unless it is specified 
whether the nitrogen, the phosphorie acid, and the potash are 
derived from the better prized material, these ingredients are 
considered as being derived from the baser ones when calewlating 
values. 
Knowing these values, it is easy, when furnished with an 
invoice certificate, to determine the real value of the manure 
offered. Thus a mixed fertiliser contains— 
Nitrogen (as Sulphate of Ammonia) .. 4 per cent. 
Phosphoric Acid—Water Sol. a wage OD re 
6 » Citrate Sol. ne ine OD ss 
a »  Losoluble ... re 3 a 
Total Phosphoric Acid ... ey 10 - 
Potash, Muriate irs ss és ae 4 4 
This statement is treated as follows :— 
4 per cent. Nitrogen and Sulphate of Ammonia, sd. 
at 16s. Hi tas ae aus ate 3 04 ~=«0 
5 per cent. Phosphoric Acid, soluble, at 7s. 115 0 
2 es 5 Citrate, sol., at 5s. ... 010 0 
3 a me Insol., at 3s. 0 9 O 
4 35 Potash, at 7s. wee 1 8 0 
47 6 «(0 
