EXPERIMENT STATION BULLETINS. 577 



SMUT REMEDIES AND FORMALDEHYDE SOLUTIONS 



Special attention was given to these preparations dnring 1917. Several 

 proprietary compounds were on sale in the State in violation of the in- 

 secticide law in that they were not labelled so as to show the active in- 

 gredients. All of these preparations were found to be. essentially, solu- 

 tions of formaldehyde (formalin) to which had been added, in some cases, 

 coloring matter or one or more of such materials as carbolic acid, copper 

 sulfate, aloes, pix liquida, sodium hydrate, green soap, etc. 



The claim was made that the addition of these materials increased the 

 efficiency of the formalin. However since the formalin treatment when 

 properly conducted is practically 100 per cent efficient it is difficult to 

 understand how this could be much improved. 



The attention of the various manufacturers was called to the require- 

 ments of the law in regard to the labelling and it appears that they are all 

 now complying with the law or have gone out of business. 



Sixteen samples of formaldehyde solution (formalin) which was being 

 sold for grain treatment were collected. Very few of these were properly 

 labelled and the dealers were notified to comply with the law in this re- 

 spect. The names of the manufacturers of the various samples could not 

 be obtained and in the following table the dealer's name is given. 



The solution of formaldehyde is usually sold under tlie trade name, for- 

 malin, and is supposed to be of 40 per cent strengtli. This generally 

 means 40 per cent by volume which corresponds to .'5G.8 per cent by weight. 

 The results in the following table are given in per cent by weight. 



Eight of the samples were found to contain more than '^G per cent of 

 formaldehyde and four samples contained more than 35 per cent but less 

 than 30 per cent formaldehyde. Two samples were less than 34 and more 

 than 32 per cent formaldehyde while two contained less than 30 per cent. 

 There is probably no very great difference in efficiency between formalde- 

 hyde solutions of 35 and 30 per cent formaldehyde but as between 30 and 

 30 per cent there would be considerable los.s of efficiencv. 



