80 HYDROCYANIC-ACID GAS FUMIGATION IN CALIFORNIA. 



GENERAL CAUTIONS. 



Hydrocyanic-acid gas is one of the most deadly of gases, so that 

 considerable care is necessary in its use. Such exaggerated cautions 

 have been written, in view of its poisonous properties, that the public 

 at large have come to believe that a single whiff of tins gas will 

 produce the immediate death of an individual. This erroneous idea 

 should be corrected. A whiff of the gas will not cause immediate 

 death: neitherwill two or three whiffs. If subjected to a strong gas 

 for a minute or two. undoubtedly a person would be overcome. The 

 writer has never yet had a record of a person killed by hydrocyanic- 

 acid gas while fumigating. In California, men work around tents 

 every night for weeks at a time without any ill effects. During these 

 operations they are breathing the gas in a diluted form much of the 

 time. Repeatedly field men are seen sitting, either to rest or eat 

 their lunch, on the edge of a tent covering a tree which had been 

 dosed a few minutes previously. The writer has personally stood 

 within a foot of a generator for an hour at a time, taking tempera- 

 tures of the escaping gas as different dosages were tried out, some 

 of which would be in excess of a pound. Frequently the wind would 

 waft the fumes into his face. Outside of an occasional dizziness and 

 headache, no serious results were experienced. Scores of similar 

 cases could be cited. 



These experiences have been mentioned, not with the idea of 

 tempting people to be careless in the use of this gas, but merely to 

 correct the erroneous conception that a whiff of the gas will cause 

 instant death. This gas is most dangerous, and the writer has seen 

 men who were subjected to a great strength of it for several minutes 

 at a time overcome by its effects, although they revived later. If the 

 proper precautions are taken the careful operator will run no risk 

 whatever. Place the charge in the generating vessel with extended 

 arm so that the head of the operator is away from the escaping gas. 

 Being lighter than air, the gas rises straight up in a narrow column 

 until several feet above the ground. As soon as the dosage has been 

 set off, quickly leave the tent or room, whichever it may be. If this 

 procedure is followed there is no danger of ill effects to the operator. 



