8 INJURY TO VEGETATION BY SMELTER FUMES. 



after drifting over one high hill, have an uninterrupted sweep down 

 the valley of the Sacramento. In an easterly direction the fumes 

 pass, in the main, down the valley of a small stream and finally find 

 outlet at the river, where they have a nearly uninterrupted sweep in 

 both a southerly and an easterly direction. 



Immediately surrounding the smelting works practically all vege- 

 tation was entirely 7 dead. Nothing was left of the trees but the bark- 

 less trunks, and no green grass was to be seen. In a northerly direc- 

 tion, as far as Copley (about 3| miles), it was noted that large numbers 

 of trees were either dead or dying, this being especially true of pines. 

 Even for a mile and more beyond Copley numbers of the trees were 

 dead, and others though living'did not appear to be strong and healthy. 

 In an easterly direction and beyond the river the damage was not so 

 great, yet even here for 2-j- to 3 miles and more the leaves of nearly 

 all oak trees were turning brown and dying. 



In a southerly direction great damage was observed to all classes of 

 trees for about 3 miles, or to the southern road running between 

 Redding and Shasta. Still farther south, in Happy Valley (about 9 

 or 10 miles distant from the smelter), it was observed that large num- 

 bers of fruit trees, especially the peaches, which are very sensitive to 

 injurious substances, were badly injured. This injury showed itself 

 ii the following w^y : The leaves would turn prematurely red and 

 yellow (just as they do when sprayed with Paris green containing too 

 much soluble arsenic) and drop off of the branches, leaving the fruit 

 exposed, sometimes for 2 to 3 feet from the end of the branch. The 

 trees did not appear to be suffering from a lack of water, nor from 

 disease or insect pests, so that this injury was very likely due to the 

 sulphur dioxid fumes. Further than this, several ranchers were 

 interviewed, who said that when the wind was in a southerly direc- 

 tion the odor of the fumes could be plainly detected in their orchards 

 and that soon after this the leaves usually began to drop. In a west- 

 erly direction great damage to a large number of trees was observed 

 all the way to Whisky Town, about 5 miles from the smelter. Beyond 

 Whisky Town the injury was not so great, but for a mile and more 

 some of the trees were dead and large numbers did not appear to be 

 vigorous and healthy, i. e., they 7 were stunted in growth, had much 

 less than the normal amount of foliage, and what foliage there was 

 did not have a healthy green color. 



Before describing the investigation as made, the principles of 

 elementary chemistry involved will be given for the benefit of readers 

 who, though not chemists, may desire to use the data. 



CHEMICAL PRINCIPLES UNDERLYING THE INVESTIGATION. 



The ore used by the Mountain Copper Company consists largely of 

 sulphids of iron and copper. During the process of extracting the 

 copper it is first calcined in appropriate furnaces to get rid of a large 



