352 Journal of Agriculture, Victoria. [lo May, 191 i 



Of this varied list, whicli is by no means exhaustive, oil cake is per- 

 haps the most interesting substance. Though it is one with which we 

 are quite unfamiliar from a manure standpoint here, it is employed to 

 an enormous extent in southern France. 



The neighbouring town of Marseille may be said to be the oil mill of 

 France. It is the head-quarters of the oil extracting and soap making 

 industries of the country and imports enormous quantities of oil containing 

 seeds, the by-products from which are an important source of nitrogen 

 and organic matter, for the agriculture of the neighbouring country. After 

 treatment by ordinary pressure the last traces of oil are removed by ex- 

 traction with bi-sulphide of carbon. The oil cake thus treated is known 

 in French as Tourteaux sulfur es. It has the advantage of decompos- 

 ing more rapidly than greasy cake, whilst its manure value is slightly 

 higher. 



Foex gives the percentage of nitrogen and phosphoric acid of .several 

 kinds of oil cake as follows : — 



Nitrogen. Phosphoric acid. 



Colza (Europe) ... ... ... 4.92 ... 2.83 



Castor oil (crude) ... ... ... 3.67 ... 1.62 



Castor oil (skinned) ... ... ... 7.42 ... 2.26 



Sesame (black) ... ... ... 6.34 ... 2.03 



This oil cake is employed at the rate of about i6 cwt. per acre in 

 Herault ; it is usually absorbed entirely during the year which follows 

 its application. Its low potash contents makes it advisable to give simul- 

 taneously with it, potash salts, say from 360 to 450 lbs. per acre of 

 chloride (muriate) of potash, sulphide of potassium or sulphate of potash. 



The two kinds of oil cake which figure most frequently in manure lists 

 are cotton .seed and sesame {Sesamum indicum) the prices being respectively 

 about ;^5 1 28. and ;£6 per ton at Marseille. 



The importance of these by-products to French agriculture should be an 

 argument in favour of the cultivation of oil bearing plants. Were oil 

 cake available, at a reasonable price, it would be a great boon to our 

 northern agriculture, as a source, not only of nitrogen, but also of 

 organic matter, so necessary under our hotter sun. 



The Popularity of Gypsum. 



This is another striking fact. We have seen the inclusion of plastei 

 or gypsum in the manure formulae of both Professor DegruUy and Pro- 

 fessor Lagatu. It is, in fact, almost invariably included in French vine 

 manure fonnulge. Though its exact mode of action seems somewhat 

 obscure, its influence in increasing production is very generally admitted. 

 Is this owing to its sulphuric acid? Does it act as a source of sulphur? 

 Possibly. Lime is not nearly so extensively employed as gypsum in the 

 manuring of Herault vineyards. 



The latter is far more soluble in water than carbonate of lime — about 

 166 times as soluble, in fact. Lime becomes carbonated and loses most 

 of its solubility, soon after application, -whereas gypsum, remaining 

 unchanged, its diffusion in the .soil would continue. Gypsum is worth 

 8s. per ton in France. 



M. Zacharewicz,* in a recent article on the subject, after recalling 

 Franklin's experiments in America some 60 years ago, which first led to 

 its extensive use, points out that, when employed alone, it proved dis- 

 appointing and was ultimately given up. 



» Revue de ViticuUure, 21 January, 1909 . 



