12 



BULLETIX 1027, U. S. DEPAETilEXT OF AGPJCULTUEE. 



12 of the samples and 0.1, 0.1, and 0.2 milligram of arsenic per liter 

 in the other three. He attributed the higher content of arsenic in 

 the last three samples to the fact that the wines had been sulphured. 

 If, as held by Gautier and Clausmann (55), a normal wine contains 

 about 0.01 milligram of arsenic, he felt that the arsenical treatment 

 of vines will introduce into the wine less than 0.03 milligram of 

 arsenic per liter. Mestrezat (87) considered that the only danger 

 from the use in viticulture of arsenical insecticides occurs when 

 they are placed near other substances which resemble them so closely 

 as to be easily mistaken for them. In 1906 Forbes (39) reported 

 36.6 and 32.9 parts of arsenious oxid per million in peelings of apples 

 sprayed the preceding day with lead arsenate and 40.1 parts of 

 arsenious oxid per' million in peelings of apples gathered two months 

 after being sprayed heavily with lead arsenate. He considered that 

 lead arsenate could be substituted for the more common insecticide 

 sprays if discretion were exercised in its use. In 1910 Giinther (60) 

 reported the results given in Table 3 on fruits that had been sprayed 

 once with a mixture containing 300 grams of sodium arsenite and 

 425 grams of lead acetate per 100 liters. 



Table 3. — Residue on fruits sprayed once with mixture containing 300 grams of sodium 

 arsenite and 425 grams of lead acetate per 100 liters (Giinther). 



Gooseberries 

 Currants. . . 



Pears 



Apples 



Do 



Days 

 elapsed 

 after spray- 

 ing. 



Arsenic. 



Lead. 



Milligrams per 100 

 grams. 



39 

 80-106 

 80-106 

 SO-106 



1.000 

 7.140 

 .129 

 .074 

 .057 



2.16 

 16.70 



Trace. 

 0.017 



He reported the results given in Table 4 on fruits dusted once 

 with a mixture consisting of 2 parts of freshly slaked lime, 4 parts* 

 of sulphur, and 1 part of Paris green. 



Table 4. — Residue on fruits dusted once with a ynixture consisting of 2 parts of freshly 

 slaked lime, 4 parts of sulphur, and 1 part of Paris green {Giinther). 





• Days 

 elapsed 

 after dust- 

 ing. 



Arsenic. 



Copper. 



Gooseberries 



39 



39 



39 



39 



80-106 



80-106 



80-106 



80-106 



24 



24 



24 



Milligrar 



gra 



0. S.3iOO 



2. 1200 



1.6100 



1.5300 



.0720 



.0420 



.0084 



.0420 



.2000 



.3200 



.5000 



ns per 100 

 ms. 



0. 560 



Do .. . 



.930 







Do 



.870 



Pears. ... 



.240 





.067 



Do .. 



.095 



Do 



.011 



Sweet cherries 



.160 



Sour cherries 



.250 



Plums 



Trace. 







