11 



with 3 cc of the caustic potash or soda solution, following this by 50 cc of 

 hydrogen peroxid free of sulphates. Heat on the steam bath for just one-half 

 hour and then acidify with hydrochloric acid, precipitate with barium chlorid 

 In the ordinary manner in boiling solution, and finally weigh as barium 

 sulphate. 



BIBLIOGRAPHY. 



I ..Mowing is a list of the publications which explain the advantages of the 

 above methods for examining the several classes of insecticides and fungicides 



mentioned : 



Tin- Adulteration and Analysis of the Arsenical Insecticides. J. Am. Chem. 



1900, 22, [9], 



The Analysis of Arsenical Insecticides. J. Am. Chem. Soc., 1900, 22, [10], 

 TO"). 



The Composition and Analysis of London Purple. J. Am. Chem. Soc., 1900, 

 2i>, [I'-' I- 8 



:<on dt' kefeiee on I nsrrt icioles and Fungicides. Proceedings of the Asso- 

 iatiou of < Mlicial Agricultural Chemists for 1900, p. 139. 



Soluble Arsniiou* o.xid in Paris < liven. .1. Am. Chem. Soc., 1901, 23, [2], 

 111. 



\ 1,'apiil Method for HM- Determination of Arsenious Oxid in Paris (ireen. 

 I. Am. Chem. Soc., HMH, :>.>, [7], 185. 



eport of the Keferee on Insecticides and Fungicides. Proceedings of the 



iatii'ii of <Mlicial Agricultural Chemists for 1901, p. 87. 



The Chemical Composition of Insecticides and Fungicides. U. S. Dept. Agr., 

 Bureau of Chemistry, I5ul. >S. 

 Keport of the Keferee on Insecticides and Fungicides. Proceedings of the 



:;iion of < Mlicial Agricultural Chemists for liMrJ, p. 158. 



A Modification ()| tm> A very-P.eans Method for Determining Total Arsenious 

 Kid in Paris Green. .!. Am. Chem. Soc., 1903, 25, [9], 963. 

 A Comparative Study of Methods of Determining Formaldehyde. .1. Am. 

 hem. So,-., I'M):;. i'.5, [10], lO'JX. 

 I;. -port of the Ilefeive on Insecticides and Fungicides. Proceedings of the 



ition of (Mlicial Agricultural Chemists for 1903, p. 15">. 



l;.-pi'i-i of the Uefeive on Insecticides and Kungicides. Proceedings of the 

 iatioii of < Mlicial Agricultural Chemists for I'.'OI, ]>. !.'>. 

 niation of Nicotin in Presence of Pyridine. J. Am. Chem. Soc., 1904, 26, 

 \ i::. 



Tin- Metermiiiatioii of I.ime and Sulphur in Solutions of Sulphides and Poly- 

 lphi.k- u-e-1 as liiserticiil-<. Proceedings of the Association of OHicial Agri- 

 ltural C|,,.|i.i>ts for I'.xil. p. KM. 



!landel>analyse \on l-'nnualdi-liyd. /ts. anal. Chem., I'.tn:,, //, [1], ];{. 

 \ <iinl\ of the llydrti^en lVnxid Method of Determining FormaMehyde. 

 Am. Ch( in. Soc., September, 1905. 



J. K. II \Y\VUOD, 

 c/n>f. Miscellaneous Laboratory. 



\pplo\r.l ; 



.IAMKS WILSON, 



Sect-' i 'in i. 



W.\-]IIN;TOX, D. ('.. I ttgust 21, 1905. 



