54 INSECTICIDES AND FUNGICIDES. 



PAR'OIDIUM. 



[Serial No. 23721.] 



Composition of Par' Oidium. 



Per cent. 



Ash insoluble in hydrochloric acid 7. 10 



Carbon dioxid 2. 88 



Sulphur trioxid 17. 12 



Ferric oxid *!;..:, 10. 63 



Calcium oxid 15. 58 



Magnesium oxid 73 



Sulphur 19. 12 



Tobacco, water of hydration, and hygroscopic (by dif- 

 ference) .... 26.84 



100 



This substance appears to be principally composed of gypsum, sul- 

 phur, and ferric oxid, with smaller quantities of sand, tobacco, etc. 

 Nothing appears to be present besides the sulphur and small amount 

 of tobacco that gives it any value as an insecticide. As far as its sul- 

 phur content goes, this compound would be applicable to surface mil- 

 dews. The same amount of sulphur and tobacco, however, could be 

 purchased for much less than 30 cents, the cost of a can of this pre- 

 paration. 



FLECK'S LICE EXTERMINATOR. 



[Serial No. 23722.] 



Composition of Fleck's Lice Exterminator. 



Per cent. 



Insoluble in hydrochloric acid 4. 20 



Carbon dioxid 9. 56 



Sulphur trioxid .' 1. 99 



Ferric oxid 1. 43 



Calcium oxid 31. 90 



Magnesium oxid 21. 61 



Volatile matter, other than carbon dioxid 29. 88 



100. 57 



The volatile matter consists of naphthalene, tobacco, pink coloring 

 matter, and water of constitution and hygroscopic moisture. This 

 sample evidently consists of partially air-slaked lime mixed with naph- 

 thalene and tobacco, and colored with a pink dyestuff. In so far as 

 the naphthalene and tobacco are concerned, this compound will doubt- 

 less drive away lice. The lime also has weak insecticidal properties. 



GRUB AND CANKER WORM EXTERMINATOR. 

 [Serial No. 16 I. & W.j 



Method of analysis. Weigh out about 10 grams of the sample in a 

 beaker. Treat with petroleum ether, pouring the wash ether through 

 a weighed filter, and continue washing till all oil is removed. Dry fil- 

 ter and contents and weigh. The contents of the filter represents 



