376 JouENAL Of the Department of Agbiculttjeb. — Oct., 1922. 



Mixing Fertilizers. 



I nchdii (jd . — Can I saiVl\ mix the iullow i ii^ ^ W'liat \\(uild \)v llic 

 iTsuItiiig' anaJysis, and would the mixture bo isuitable for niealii'S on 

 a poor sandy vSoili" 2(J(K) lb. blood lueal (11'5 per cent. iiitro<»en), 

 500 lb. muriate of ])otash (GO per cent.), 2000 II). supori)bospl)ate 

 (water soluble phosphoric oxide IT'G, citric soluble i)hosphoric oxide 

 17"5; total phosphoric oxide 18"0 per cent.). 



Cedara School of Agiiculture replies: The mixture would have 

 tlie following- composition: — Nitrogen 5"1 per cent., ]iotasli G'T per 

 cent., phosphoric oxide soluble in water 7"G per cent., i)hosphoric 

 oxide .sojublfe in citric acid 7'8 per cent., total phosphoric oxide 8 per 

 cent. TbJs mixture would be suitabhe for the soil. For most crops 

 and soil there is no choice between the sulphate and the jnuriate of 

 potasli, but it is usually considered that the sulphate is preferable 

 foi' tbe ])otato and tobacco crops. 



Wooden Stave Silos. 



Roi-etta. — '' AVould you advise the erection of a uooden stave 

 siio on our farm at an .iltitude of 4500 feet? We fear shrinkage will 

 be too great at such an altitude." 



Cedara School of Ar/ncuUure replies: If ]t is a matter of freez- 

 ing, I would say that freezing is just as likely to take place inside 

 any other design of silo. Provision is made on all stave silos to 

 take up shrinkage. 



Anthrax Spore Vaccine. 



Sencldl. — Do you recommend the Australian Spore Vaccine? I 

 notice it is advertised to keep cattle ir)imune for life. 1 have always 

 got my spore vaccine from you, and would like your advice. 



The Director of Vcleriiiarjj Edvcatiou and Researcli replies : 

 I regret that it is not possible for me to recommend the use of the 

 Australian vaccine in preference to our own, for the simple reason 

 that there is no evidence whatever to show that it is superior in any 

 way to the spore vaccine prepared by this Division. What makes it 

 impossible for me to recommend the use of any imported vaccine to 

 our farmers, is that we have no control whatever over the preparation 

 of such vaccines. Anthrax vaccine is made from living organisms, 

 and hence the most careful control of each stage in its preparation 

 is essential, if one wishes to be quite sure that it is safe for use and 

 will produce the necessary immunity. Such control can only be 

 exercised when one prepares the vaccine oneself, as is done in tlie\ 

 case of our own spore vaccine. Our experience with the Australian 

 vaccine is that it produces large swellings in some animals, particu- 

 larly in horses, and that it is not safe to use in goats. The claim put 

 forward that the Australian vaccine will protect animals for life 

 cannot be taken seriously. We know from experience that the im- 

 munity set up by this vaccine and by our own will last only for about 

 9-12 months, and it is for this reason that we advise farmers to 

 inoculate their stock running on infected farms at least once a year. 



