I0I2 



Notes on Manures. 



[JAN.^. 



considered distinctly superior for certain valuable crops such, 

 as potatoes, malting barley, etc., and it has no adverse effect 

 on the tilth of heavy soils where nitrate of soda may be harmful. 

 On the basis of chemical composition, 76 lb. sulphate of 

 ammonia contains as much nitrogen as 100 lb. nitrate of 

 soda, but the nitrogen in sulphate of ammonia is not so 

 effective lb. for lb. as that in nitrate of soda ; in fact, i lb. 

 nitrogen in nitrate of soda is as effective as 1*035 lb. nitrogen 

 in sulphate of ammonia ; and on an average of all crops 100 lb. 

 of ordinar^^ nitrate of soda are about as effective as 80*3 lb. of 

 sulphate of ammonia. These figures, however, take no account 

 of the special uses of the two substances to which reference 

 has just been made. 



Prico of Mixed FertiUsers. — A correspondent, interested in the 

 fertiliser trade, has suggested that the comparison made in 

 the December notes between the home-made and the purchased 

 mixed fertiHsers is unfair, for the following reasons : — 



I. That the receipt given for the home-made fertiUser would 

 not as a matter of fact contain the same constituents as the 

 proprietary article in question ; he offers two receipts which 

 would cost, respectively, £14 4s. 3</. and £14 5s. '^d. instead of 

 £13, the cost of the home-made mixture. The proprietary 

 article was offered at £19. 



The correspondent claims that the manufacturer in making 

 the mixture has to pay double carriage, and in all probability 

 has to use a considerable number of new bags, items which 

 would account for some of the difference betweea the £14 5s. 

 and the /19. 



The composition of the various mixtures is as follows : — 



Manure. 



Proprietary 

 Article 

 quoted. 



Home-made 

 Mixture 

 suggested 

 in Dec. Notes. 



The Correspondent's 

 Mixtures. 



A. 



B. 





20 cwt. 



20 '75 cwt. 



22-5 cwt. 



20 cwt. 









£14 4S. 3d. 







cwt. 



cwt. 



cwt. 



cwt. 





1-4 



I -41 



1-59 



1-59 



Soluble phosphate 



4*o 



3-97 



4-05 



4*07 



Insoluble phosphate . . 



0-5 





0-29 



0-3 



Sulphate of potash 



1-6 



:78 



1-8 



1-8 



* The mixture would cost £12 los. 7d. per ton, but 2of cwt. would be necessary to supply the 

 same amoimt of plant food as is contamed in. i ton of the proprietary article, and the cost of 

 2o| cwt. is £13. 



It will be observed that the home-made mixture suggested 

 in the December notes approximates closely to the proprietary 



