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in the spring, mixed with some dry, well-ground material such as 
sand, earth, or other fertilisers, so as to ensure its even distribu- 
tion. It is suitable for using in mixtures with superphosphate. 
Nitrate of Soda—As imported from Chili, contains rather 
more than 15 per cent. of N. or 18 to 19 per cent. ammonia. Its 
price is high in Australia. More soluble than sulphate of am- 
monia, and for this reason especially useful in a dry season, ow- 
ing to its being deliquescent. Applied at the rate of 1% to 1% ewt. 
per acre in the spring, mixed with some dry, well-ground material, 
so as to ensure its even distribution. Experiments I have conducted 
in manuring vines with this fertiliser have given very good results. 
The Combined Use of Sulphate of Ammonia and Nitrate of 
Soda.—It is well known that the continued use of sulphate of am- 
monia on soils deficient in carbonate of lime is calculated to give 
rise to acidity of the soil; at the same time it is also known that the 
continued use of nitrate of soda gives rise to an alkaline condition 
in the soil. The suggestion has therefore been made, that by using 
a mixture of sulphate of ammonia and nitrate of soda in proper 
proportions, a neutral condition of the soil may be maintained, 
so far as the use of these fertilisers is concerned. 
The correct proportions to secure this result are, in round 
numbers, 100lbs. nitrate of soda to 78lbs. sulphate of ammonia; or 
100lbs. sulphate of ammonia to 129Ibs. nitrate of soda; or, approxi- 
mately, 4 parts of nitrate of soda to 3 parts of sulphate of am- 
monia. 
Relation between Nitrogen and Ammonia.—Soil or manure 
analysis often express the nitrogenous contents as nitrogen or as 
ammonia. And in order to better understand the difference between 
the amount of each, it is useful to remember that 17 parts of 
ammonia (NH,) contain 14 of nitrogen (N) and that 66 parts of 
pure sulphate of ammonia, or 85 parts of nitrate of soda, also con- 
tain 14 parts of nitrogen. Most nitrogenous manures, however, are 
very expensive, and whenever it can be arranged green manuring 
which will be referred to below, offer the cheapest way of adding to 
the store of humus and of nitrogen in the ground. Exeess of 
organic nitrogenous manures, it should be borne in mind, are often 
productive of harm, and eause such diseases as “die back” of the 
trees. In white ant infected districts it must also be used with 
caution. “I have used sheep manure for orange trees,’ writes a 
Narra Tarra fruit grower; “it acts very well, but proves a hotbed 
for white ants.” 
PuospHorvs is, next to nitrogen, the most costly ingredient of 
fertilisers, in which it oceurs in the form of phosphates of lime, 
iron, and aluminium, or, in case of superphosphates, partly as free 
phosphoric acid. In good soils it rarely exceeds -2 per cent. 
The trade uses with regard to phosphoric acid several terms 
which to the layman are not very familiar, thus:— 
