INJURY TO CATTLE ABOUT ANACONDA. 



29 



It is a matter of general knowledge that a large percentage of the 

 sulphur in the ore is given off as sulphur dioxid in the usual smelter 

 operations. If the ores given in Table IV are fairly representative 

 samples of the material smelted at Anaconda, and if 8,000 tons of 

 ore are handled each day, it will at once be seen that a tremendous 

 quantity of sulphur dioxid is dis-tharged into the atmosphere. Har- 

 kins and Swain ^ have studied the composition of the smelter smoke 

 from the Washoe smelter and found that the average amount of 

 sulphur dioxid and trioxid given off per day is 4,030,000 pounds and 

 447,000 pounds, respectively. Unfortunately these authors do not 

 give the composition and quantity of the ore smelted during the time 

 that the experiments Avere made, so that it is impossible to calculate 

 what percentage of the sulphur present in the original ore was dis- 

 charged through the stack as sulphur dioxid and trioxid. 



INJURY TO CATTLE BY ARSENIC IN THE VICINITY OF THE 



WASHOE SMELTER. 



A claim made by the farmers, which required investigation, was 

 that enough arsenic is given off from the smelter to settle on the sur- 

 rounding forage crops and so poison the cattle. To determine this 

 it is first necessary to show that the ores reduced at the smelter con- 

 tain arsenic. Examinations of several samples of ore from mines 

 which partly supply the smelter gave the following results : 



Table V. — Arsenic content of ore samples. 



If we reject the first sample in Table V as exceptional and consider 

 the other ores as representative of those received at the Washoe 

 smelter, it will be seen that such ores contain 0.85 per cent of arsenic. 

 At this rate, if 8,000 tons of ores per day are smelted, 08 tons of ar- 

 senic enter the plant each day and, according to the officers of the 

 smelter, only 2 tons of white arsenic are recovered daily. This, 

 of course, does not mean 2 tons of metallic arsenic, but for conveni- 

 ence in discussion, it will be considered as such. There remain, there- 

 fore, CO tons of arsenic to account for, which can only escape in a 

 volatile form in the fumes, or be carried off in the tailings and slag. 

 A determination of arsenic was made in two samples taken from the 

 dump in which 0.11 and 0.07 per cent were found, or an average of 



« J. Amer. Cliem. Soc, 1907, 29: 970. 



