6r- 



Journal of Agriculture. 



[lo Oct., 1910. 



ANALYSES OF SAMPLES OF ARSENATE OF LEAD. 



p. Rankin Scott, Cliemist for Agriculture. 



The effectiveness of arsenate of lead as a spray is, eacii year, becoming 

 •ijetter known, and consequently it is displacing the more common arsenical 

 preparations which have been used in the past by fruit-growers. Manu- 

 facturers have evidently realized the fact that a demand is assured for 

 this insecticide, and have placed on the market a number of brands which 

 are new to Victorian orchardists. Last year various samples were collected 

 by me, and the analvses were published in the December Journal for the 

 guidance of growers. 



I have again obtained samples of brands on the Victorian market and 

 the result of the analysis is given below. The locally made article is well 

 represented, and included in the list are preparations made in South Aus- 

 tralia, England, Scotland, United States, and Germany. It will be 

 noticed that, although the preparations vary in composition, they are true 

 to name, and 1 am of opinion that under ordinary circumstances their use 

 will be found to be effective and harmless to foliage. It is important, 

 however, that the best water obtainable be used in mixing. The water 

 should be free from dissolved mineral .salts, such as carbonates and 

 chlorides, which, when present in the water, act more or less as a solvent 

 upon the lead arsenic and consequently damage may result to the foliage, 

 bv burning. It is therefore safer to use rain water and so avoid the danger 

 referred to. 



By the analy.ses now published the grower is enabled to .see that the 

 material with which he is spraying is chemically of good quality. The 

 mechanical condition and the respective merits of the brands can. however, 

 best be judged by the orchardist. He can note points of advantage, such 

 as the property of readily mixing, and whether the solution remains 

 cloudy by retaining the arsenate in suspension after being diluted and pre- 

 pared for use, thereby rendering the spray capable of being eve:ily dis- 

 tributed over the foliage. 



Sample. 



Swift's ... 



Ferguson's " Elephant Brand " 



E. De Haen 



Sherwin-Williams 



Bickford's " Our Jack " ... 



Aus. JCxp.and Uhem. Co.'s "Federal" 



Jenkins' "Austral' 



^lyth's " Bluebell " 



Vreeland's " Electro " 



Jaques Fisher and Co.'s "Cobra '" ... 



Edward and McGuinness' "Red 



Seal" 

 Walter Vo&s and Co. Ltd. " Carllon "' 



Per cent. 

 41 -89 

 4018 

 67-67 

 55 84 

 50 ■ 1 .S 

 49 -.50 

 21 .37 

 44 05 

 33 •66 

 43-65 



49-07 

 41-78 



Total Total 



Arsenic Lead 



Oxide. Oxide. 



Per cent. 

 1600 

 14-89 

 10 09 

 10 61 

 l:i 91 

 13 46 

 16 35 

 17-98 

 20 - 25 

 15-58 



15-08 

 17-62 



33 02 

 36 69 



Water 

 Soluble 

 Arsenic 



Oxide. 



cent. 



58 



19 



18 



06 



16 



72 



11 



13 



IS 



19 



017 



0-87 



Water 



Soluble 



other than 



Arsenic 



Oxide. 



Per cent. 

 3 72 



