vni. D. 1 



Jones: The Cigarette Beetle 



29 



SMOKING EXPERIMENTS 



In view of the fact that there was thought to be a possibility 

 of the deposition of cyanogen in the cigars by the cyanide treat- 

 ment, several experiments were carried on to determine this 

 point. 



Cigars and leaf tobacco were treated with the requisite min- 

 imum of cyanide, 32 grams per cubic meter, and after treat- 

 ment, analyses by chemists of the Bureau of Science showed the 

 presence of hydrocyanic-acid gas in both the treated and un- 

 treated tobacco, but the amount was so small that in samples of 

 less than 400 grams no quantitative determination could be made. 

 The hydrocyanic-acid gas in 50 grams of treated tobacco was 

 administered to a guinea pig without ill effects. 



A series of treated and untreated cigars was smoked by means 

 of ah aparatus (Plate VIII, fig. 2), and the volatile products 

 of combustion passed through a solution of silver nitrate, which 

 was to fix the cyanogens which would ordinarily be taken in 

 by the smoker, and afterward analyzed quantitively. Cigars 

 of various brands were fumigated with cyanide and smoked 

 simultaneously with a corresponding number of untreated cigars 

 of the same brand. Hydrocyanic-acid gas was obtained in each 

 case, and not infrequently the untreated cigars gave more of 

 this product than did the treated. Any differences which really 

 exist between the yield of hydrocyanic-acid gas from the treated 

 and untreated cigars are so small in comparison with the total 

 yield that they are negligible as shown by Table XX, which 

 gives the actual amount of the tobacco smoked and of cyanides 

 found. 



Table XX. — Hydrocyanic-acid gas (HCN) in treated and untreated cigars.* 



Number 



of 

 cigars. 



Cyanide treatment. 



Tobacco 

 actually 

 smoked. 



HCN gas 

 found. 



HCN per 

 gram of 

 tobacco 

 smoked. 



Average 

 HCN per 

 gram of 

 tobacco 

 smoked. 



Remarks. 



Potas- 

 sium 

 cyan-de 

 per cubic 

 meter. 



Duration. 



12 



12 

 12 



Grams. 

 32 



32 



none 



Hours. 

 24 



24 



none 



Grams. 

 78.40 



8L17 



74.2 



Grams. 

 0.0648 



0.1049 



0.0849 



Grams. 

 0.000826 



0. 00129 



0. 00114 



Grams. 

 0. 00106 



Cigars aerated 5 days 



before smoking. 

 Cigars aerated 10 days 



before smoking. 

 Cigars not treated and 



used as a check. 



0.00114 



■ Analyses by F. B. Beyer, division of general, inorganic, and physical chemistry, Bureau of 

 Science 



