| 1 May, 1900.] QUEENSLAND AGRICULTURAL JOURNAL. 4.21. 
| EXPLANATION OF TERMS USED IN DISCUSSING FERTILISERS. 
Complete Fertiliser is one which contains the three essential fertilising 
| “onstituents—i.e., nitrogen, phosphoric acid, and potash. 
Nitrogen exists in fertilisers in three distinct forms—viz., as organic matter, 
48 ammonia, and as nitrates. It is the most expensive fertilising ingredient. 
Nitrates furnish the most readily available forms of nitrogen. The most 
‘ommon are nitrate of soda and nitrate of potash (saltpetre). 
Phosphoric acid, one of the essential fertilising ingredients, is derived from 
| Materials called “phosphates.” It does not exist alone, but in combination, 
} Most commonly as phosphate of lime in the form of bones, rock phosphate, and 
| Phosphatic slag. Phosphoric acid occurs in fertilisers in three forms—soluble, 
_| verted, and insoluble phosphoric acid. 
= Soluble phosphoric acid is that form which is soluble in water and readily 
taken up by plants. 
Reverted phosphoric acid is that form which is insoluble in water, but still 
| Teadily used by plants. 
Available phosphoric acid is the soluble and reverted taken together. 
. _ Superphosphate.—In natural or untreated phosphates the phosphoric acid 
insoluble in water and not readily available to plants. Superphosphate is 
| Prepared from these by grinding and treating with sulphuric acid, which makes 
© phosphoric acid more available to plants. Superphosphates are sometimes 
| “called “ acid phosphates.” 
| .. Potash, as a constituent of fertilisers, exists in a number of forms, but 
| chiefly as chloride or muriate and as sulphate. All forms are freely soluble in 
| Water, and are believed to be nearly, if not quite, equally available, but it has 
} Seen found that the chlorides may injuriously affect the quality of tobacco, 
} Potatoes, and certain other crops. The chief sources of potash are the potash 
} alts from Stassfurt, Germany—kainit, sylvinit, muriate of potash, sulphate of 
| Potash, and sulphate of potash and magnesia. Wood ashes and cotton-hull 
‘Shes are also sources of potash. 
TERMS USED IN DISCUSSING FOODS AND FEEDING STUFES. 
Water is contained in all foods and feeding stuffs. The amount varies 
trom 8 to 15 Ib. per 100 Ib. of such dry materials as hay, straw, or grain to 
0 Ib. in silage and 90 Ib. in some roots. 
é Dry matter is the portion remaining after removing or excluding the 
| Water, 
Ash is what is left when the combustible part of a feeding stuff is burned 
| ‘way. It consists chiefly of lime, magnesia, potash, soda, iron, chlorine, and 
| “rbonic, sulphuric, and phosphoric acids, and is used largely in making bones. 
) Sart of the ash constituents of the food is stored up in the animal's body ; the 
"st is voided in the urine and manure. 
Protein (nitrogenous matter) is the name of a group of substances 
} “ntaining nitrogen. Protein furnishes the materials for the lean flesh, blood, 
in, muscles, tendons, nerves, hair, horns, wool, casein of milk, albumen of 
gos, &., and is one of the most important constituents of feeding stuffs. 
Albuminoid nitrogen is nitrogen in the form of albuminoids, which is the 
Me given to one of the most important groups of substances classed together 
Mder the general term “ protein.” The albumen of eggs is a type of 
| Mbuminoids. 
Amid nitrogen is nitrogen in the form of amids, one of the groups of sub- 
| “ances classed together under the general term “protein.” Amids, unlike 
uminoids, are usually soluble in water, but are generally considered of less 
} “lue as food than albuminoids. 
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