92 Agricultural Gazette of N.S.W. [Feb. 2, 1920. 



the German product was potassium siilpliate, whereas the French product is 

 potassium chloride (muriate). As a good deal of misconception exists as to 

 the relative manurial values of these two salts, and as we shall no doubt be 

 confronted with much theoretical discussion concerning the action of chlorides 

 and sulphates on soil and crop, it will be as well to summarise shortly what is 

 known of these substances. 



It mu-st be premised that the New South Wales Department of Agriculture 

 has no practical experience in manuring with the muriate, for the reason, 

 already stated, that practically the only potash-salt available for manuring 

 hitherto has been the sulphate. 



The salt principally used in Great Britain and the United States is the 

 muriate, the main reason being undoubtedly that this is the cheapest form in 

 which potash is obtainable. Locally, up to 1904, muriate of potash was 

 sold on a guarantee of 57 per cent, potasli, and cost £13 15s. per ton. 

 Sulphate of potash with a guarantee of 52 per cent, potash was sold at 

 £13 10s. per ton. This would make the unit- value of potash in the muriate 

 4s. lOd. as against 5s. 2d. in the case of sulphate — a difference of 4d. 

 per unit in favour of the muriate. For some reason, possibly for the one 

 already suggested, after this date shipments of potash salts were confined 

 to the sulphate. Up to 1915, sulphate of potash, with a guarantee of 52 per 

 cent, potash, was quoted at £14 lOs. per ton, being a unit value of 5s. 7d. 

 Muriate was not then quoted at all. Since 1915 no potash-salt has been 

 obtainable until now. 



As inquiries are constantly made as to the value of muriate as a fertiliser, 

 and as it is being stated in some quarters that it compares unfavourably with 

 sulphate, it may be as well to state definitely that while the Department is 

 unable to speak from actual experience of the muriate, there is no reason 

 whatever to anticipate that the muriate is any way inferior to the sulphate, 

 still less that it is likely to have any injurious action on ordinary crops, as 

 has been suggested by some. 



It is the principal potash-salt used in agriculture in some countries, it is 

 cheaper than the sulphate, and in any case, it is the only one likely to be 

 available locally for some time. It is stated also that it diffuses more readily 

 in the soil than the sulphate, in other words, that it is more rajjid in its action. 



On the other hand, it must be admitted that most writers on the subject 

 affirm that it reduces the market- value of tobacco and potatoes. The most 

 definite statement of the limitations of muriate of potash as a fertiliser that 

 I have been able to find is made by J. E. Halligan, chemist in charge of the 

 Louisiana Elxperiment Station, in his book, " Soil Fertility and Fertilisers " 

 (1912). He states that tobacco, potatoes, sugar-beets and oranges are 

 crops that do not do well on large quantities of this fertiliser. The presence 

 of chlorides is regarded as objectionable in the case of these crops ; in the case 

 of tobacco the burning quality of the leaf is affected, while potatoes are 

 said to be made " waxy." 



