230 ANNUAL REPORTS OF . DEPARTMENT OF AGRICULTURE. 

 INSECTICIDES AND FUNGICIDES. 



Department Bulletin 750, "A Method for Preparing a Commercial 

 Grade of Calcimn Arsenate," and a communication on plants used 

 as insecticides, have been printed, while a paper describing the diag- 

 nostic characters of the field daisy, used as an adulterant of pyre- 

 thrum, is in press. Equipment to produce insecticides and fungi- 

 cides on a semicommercial scale has been secured, to the end that 

 ways and means to improve manufacturing processes and to devise 

 new types of useful insecticides and fungicides may be investigated. 

 In cooperation with the Bureau of Entomology, the possible value of 

 war gases as insecticides has been taken up. Phosgen and cyanogen 

 chlorid have been studied. The field men of the Bureau of Ento- 

 mology have been assisted in the work of controlling the boll weevil. 



CONTAINERS. 



The bureau was invited to designate a representative to serve upon 

 the Committee on Standard Specifications for Kitchen Ware, Mess 

 Equipment, and Flat Ware for the Army. This led to the examina- 

 tion of 61 samples of enamel ware from 26 different American manu- 

 facturers. The test most frequently used was made by boiling 500 

 cubic centimeters of 4 per cent acetic acid, the strength of standard 

 vinegar, in the vessel for half an hour. No antimony was dissolved 

 from 17 samples obtained from 9 manufacturers. Thirty-four ves- 

 sels, both white and gray ware, yielded to the solution from 0.5 to 

 2.0 milligrams of antimony. Lead was found in ware from only 

 one manufacturer. Earthenware was then examined, and in some 

 instances its glaze was found to yield to the acetic acid solution small 

 amounts of lead. 



Analyses have been made for the War Department and the War 

 Industries Board of foil used to Avrap food products and other ma- 

 terials. Some foil is pure aluminum, some is pure tin, while some 

 contains lead and tin, Avith the tin varying from 1 to 30 per cent. 

 Some of the composite foils appear to be alloys, while others con- 

 sist of an inner Isljgy of lead covered by two layers of tin. In most 

 of the instances when foil containing lead is used a waxed paper 

 wrapping is placed between the metal and the food pix)duct. 



Except in the case of phosphorus matches, there are no Federal 

 laws to protect the public against the presence of poisonous sub- 

 stances in articles of common use in the household. Many foreign 

 countries have long had such legislation on their statute books. 



Cooperation with the industry to ascertain what types of tin plate 

 are most suitable for food containers has been continued. Special 

 attention is being given to the best means of preventing the per- 

 foration of cans containing acid fruits. The results of the success- 

 ful trial in a tin mill under ordinary conditions of hydrogenated 

 oils in place of palm oil have been prepared for publication. 



A paper dealing with the use of the impact tester for fiber board 

 has been presented, and work was continued on the improvement of 

 the water-resisting properties of fiber board for fiber containers, 

 both by substituting other adhesives for silicate of soda and by using 

 external treatments which Avill not interfere with the future use of 

 the stock. A report on the various kinds of water-resistant baling 

 papers was given. 



