1(58 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 2 



difficulty nii^lit be (ivercoinc l)y havinj^' a slatted arraii^xMiicnt around 

 the inside of the house for the circulation of the eas. 



Mr. BuRGEhS: ]Mr. President, 1 want to make a statement in regard 

 to the importance of the diffusion and the penetration of gases, 

 especially concerning hydrocyanic acid gas. This sunnner I had oc- 

 casion to fumigate a large warehouse in which was stored large <|uanti- 

 ties of shelled peanuts in sacks, which were badly infested with Indian- 

 meal ^loth {PJodia iiifci-pii iiciella), and the treatment was not alto- 

 gether satisfactory. A large nnmber of worms on the outside of the 

 sacks were killed, but there were a good many live ones on the inside, 

 where the gas did not penetrate. A double charge of cyanide was nsed 

 and the room was kept closed for about eighteen hours, but still the 

 fumigation was not entirely satisfactory. I think we need to know a 

 good deal more abont the penetration and the diffusion of these gases 

 before we can attempt to use them snccessfnlly in a great many cases. 



A Member: Respecting ^Ir. Phillips' statement and some others 

 abont the diffusion of gases, we have been able to get very snceessful 

 results by putting electric fans in our fumigating houses. By placing 

 the fans in such a position in the house that they stir up the air the 

 gas is sent through the house. 



Mr. W. D. Hunter : I shonld like to say that it seems to me that 

 Doctor Hinds could add very well to the outline he has projected some 

 investigation of other fumigants. Of course, he has hit npon the two, 

 hydrocyanic gas and carbon bisnlfide, because they are in common use. 

 They are nsed by everyone everywhere, but, although he has plenty 

 to do in the investigation of those two gases, it seems to me he might 

 take up other gases. The point I am about to make is suggested by 

 what Mr. Burgess mentioned with reference to the penetrating power 

 of gases. Take the derivative of sulfur, known as Clayton gas, sulfur 

 dioxide, which has, I think, the most remarkable penetrating power of 

 any gas ever used. Investigators have succeeded in killing the germs 

 of typhoid fever in a steel cage, placed in a compres.sed cotton bale, 

 with a density of fifty-six pounds to the cubic foot. The compressed 

 bale is as hard as wood, and these germs placed in the steel cage have 

 been killed by the gas. I understand now that a very cheap and simple 

 method of generating this gas has been perfected by one manufactur- 

 ing company. They have a little affair that you can push around that 

 doesn't cost much, and it simplifies the whole matter greatly. 



President Forbes: I think Doctor Hinds' expectations must have 

 been very nicely fulfilled by this very interesting and valuable dis- 

 cussion, which has run, perhaps, as far as we can allow it. The last 

 paper on this group of subjects is by Mr. Symons. 



