12i) 



obtained of at least 80 per cent. For Jamaica the highest grade is 

 really the cheapest owing to the cost of freight (IBs. per ton). 



Basic Superphosphate. 



This is a patented article which has just been placed on the market- 

 It is by no means a novelty and the Patent rights must be doubtful 

 since we happen to know of a firm who prepared the identical article 

 some years ago and give it up as unsati-^factory in practice. 



The name of the article is not in its favour since it is not 'Basic' 

 and is not * Superphosphate.' It is prepared by treating Superphos- 

 phate with Lime ; thereby distroying the special value of the super- 

 phosphate—its solubility in water — and producing a product that we 

 are convinced is of necessity more expensive than other forms of re- 

 vei'ted phosphate ai d is by no means a Basic Phosphate with the special 

 chemical advantages of Basic Slag. A large banana planter was in- 

 duced to buy a large quantity of this article under the impression that 

 it was similar to and better than Basic Slag. I estimate a loss to the 

 purchaser of about £200 on this transaction and mention this case to 

 convince planters that the opinion of the Chemist in such matters is 

 freely available and may avoid the purchase of the wrong manure at 

 the wrong price. 



Superphosphate is undoubtedly the b( st phosphate for use on medium 

 to light soils containing adequate Carbonate of Lime. A contract with 

 a firm in Glasgow has just been made per the Crown Agents for a 

 grade of 30 per cent, soluble phosphate f.o.b. Bristol in double bags 

 at £2 lOs. Od. per ton This firm's quotations were the most favour- 

 able of a 1 rge number who were asked to quote prices for delivery 

 in April of chemical manures for the Experiments of the Board. 



Mixed Phosphate (No. 4) is an intimate mixture of 3 parts super- 

 phosphate and 2 parts steamed bone flour and is especially suitable for 

 the majority of light, alivuial soils and those deficient in Carbonate 

 of Lime 



Its value compared with Basic Superphosphate shows that, for the 

 same price in Jamaica, we obtain \ more phosphate, ^more citrate so- 

 luble phosphate and over 7o/o of water soluble phosphate in addition, 

 in ' mixed phosphate' as compared with the consignment of Basic 

 Superphosphate quoted. Steamed Bone Flour to contain 65o/o of 

 Phosphates and 2o/o Nitrogen was purchased for the Department at 

 £4 f.ob. in 1901, at £4 10s. in 1902 and at £4 14s. for the current 

 month 



I recomend the use of mixed Phosphate rather than Steamed Bone 

 flour alone. Banana planters should find this mixture with \ part 

 Sulphate of Ammonia a useful top dressing on soils in need of manu- 

 rial assistance. In some cases the Ammonia should be supplemented 

 with an equal quantity ef 9oo/o Sulphate of Potash and the mixture 

 applied at the rate of 4 to 8 cwt per acre. 



