598 Journal of Agriculture, Victoria. [10 Oct., 1918. 



for increasing this wetting power, amongst others soap, gelatine, 

 saponine, and casein. Numerous soap mixtures (containing copper, of 

 course) have been recomanended, but have since been abandoned, mainly 

 owing to the depressing action of the soap on the vegetation of the vine. 

 Gelatine is an excellent substance for the purpose, but it can only be 

 added to acid " Bordeaux " and, as will be gathered from the above, 

 this is rather difficult to prepare. Saponine is not obtainable in Aus- 

 tralia.* Casein, on the other hand, is easily procurable; it is a by- 

 product of the dairying industry, and is worth about a shilling a pound. 

 The quantity necessary to confer wetting power is one ounce for every 

 ten gallons. 



This substance is somewhat difficult to incorporate with Bordeaux 

 Mixture, to which it should not be directly added, as it would merely 

 float on the surface and form lumps. It should be separately dissolved, 

 the solution or emulsion thus obtained being added to the spray 

 mixture. 



The proper quantity of casein — 5 ozs. for 50 gallons of spray — may, 

 after thorough mixing with a couple of handfuls of slacked lime in 

 powder, be worked into a smooth cream with a little water, this being 

 further diluted to ^ gallon (a dipper full) of an emulsion rather than 

 a solution. Very little of the lime is dissolved; the greater part of it 

 remains in suspension. The whole is then poured into the 50 gallons 

 of spray mixture through a fine sieve, with thorough stirring. Casein 

 may also be dissolved in 10 per cent, soda carbonate (ordinary washing 

 soda) solution — 1 lb. to 1 gallon water. Rub to a smooth paste with a 

 little of the solution, more being added to make up ^ gallon of emulsion. 



The most convenient way to dissolve casein, however, is by means 

 of an ordinary egg-beater. The 5 ozs. casein, mixed with about its own 

 weight of dry slacked lime, is merely added to the ^ gallon of water 

 on the surface of which it floats. On turning the handle of the egg- 

 beater, the casein is rapidly sucked into the liquid, with which it becomes 

 thoroughly incorporated and soon dissolves. It may also be dissolved 

 in similar manner in 10 per cent, soda carbonate, in which case it is 

 unnecessary to first mix it with lime. 



Addition of Sulphur to Bordeaux. 



Copper fungicides are almost useless against Oidium, for which 

 sulphur is the standard treatment. A sulphuring may be saved by 

 incorporating sulphur with Bordeaux Mixture, the composition of which 

 is not afl^ected in any way thereby. The usual quantity is from 7 to 10 

 lbs. of sulphur to 50 gallons of spray mixture. The finer the sulphur, 

 the less of it will be required ; it is possible that with precipitated sulphur, 

 which is in a very fine state of division, considerably less than 7 lbs. 

 would suffice. Sulphur is somewhat difficult to mix with Bordeaux. 

 In France, special so-called " wettable " sulphurs are obtainable. Treat- 

 ment with oleic acid (1 lb. dissolved in a quart of methylated spirit to 

 1 cwt. of sulphur) renders it wettable. The oleic acid solution should 

 be mixed witli the sulphur in much the same way as bluestone solution 

 is used for pickling wheat. The sulphur may also be worked into a 



* It is possible that a similar substance might be extracted from the prickly pear. 



