Artificial Manures for Sugar Canes. 143 
Richmond Trial Plots. 
Acidulated and Ammoniated Guano, Os Ammonite, Cane Manure, 
Ammoniated Phos. Dis. Guano, Dis. Peruvian Guano, and Phosphated 
Guano, are all of much the same composition, viz. Dissolved Phosphate 
containing from 20 to 30 per cent, of Sulphate of Ammonia ; the first- 
mentioned has given the best results. Comparing these manures with 
Nitrate of Soda alone on begass land, such as we have dealt with on 
this trial, it may be seen at a glance, that it is not Phosphates or 
Potash etc., that are required, but an oxidising agent like Nitric Acid ; 
this is present in an active form in Nitrate of Soda, and it will render 
soluble any mineral matters and oxidise soluble Salts of Iron and so 
give rise to a healthy growth. I have always been of this opinion and 
I am now more fully convinced of it than ever. It is evident that the 
canes on the other plots have derived their nourishment almost entirely 
from the manure, this is the case with Nitrate of Soda also, only the 
nourishment has been obtained in an indirect manner, as I have already 
mentioned. Sulphate of Ammonia and Sulphate Mixture have done 
very well, the latter contains about 20 per cent, of Chloride of Potassium 
consequently the ash is lighter than in the other samples, deliquescent 
salts of this nature in the juice are very often the cause of " bad'' 
sugar. I am of opinion that plants absorb Nitrogen to a great extent 
in the form of Nitric Acid, hence the reason that Sulphate of Ammonia 
afts more slowly than Nitrate of Soda. When Sulphate of Ammonia is 
applied, the Ammonia has first to be converted into Nitric Acid before 
it can be absorbed. The plot manured with Ohlendorff's Guano was 
not a fair trial. I consider that this is a first-rate Guano. Sulphate of 
Ammonia adds to its effect. Superphosphate of Lime alone has not done 
well, this was to be expected. Superphosphate is very good for replen- 
ishing the soil, but its effect is slow when used by itself. I have no idea 
what is the composition of Ritchie's Manure, the results are not very good. 
It is interesting to note, that the unmanured plot has given the sweetest 
canes. Finally I am of opinion that the results on a whole are not 
good, the land at present is not in a condition for expensive manuring 
like this ; what is wanted, is deep draining and heavy " liming." 
Henrietta Trial Plots. 
These plots I think have given better results than those on Rich- 
mond ; the increase in Sugar per acre with $16 manure is about half a 
