SULPHUR TRIOXID IN FOLIAGE OF TREES, ETC. 45 
was made that could not possibly have been killed by either of these 
fires, as they had occurred too long ago, and, furthermore, the dying 
trees were hardly scorched at the base. On the north side of Silver 
Lake, also, the red firs were badly damaged and dying when this ex- 
amination was made, and yet this region had not been attacked by 
fire for many years. 
At the southern end of Georgetown Lake there did not appear to 
be any injury to lodgepole pines or red firs on either the southern, 
western, or eastern shores of the lake. To the north of the lake the 
hills showed some dead red firs, but this section was not explored. 
In brief, it may be said that in the summer of 1908 the red firs 
were injured for a distance of at least 15 to 19 miles north of smelter, 
for 114 to 14 miles east of it (where the damage from the Washoe 
smelter and the Butte smelters probably overlapped), for 10 miles 
south, and for from 18 to 19 miles west of the smelter. The injury to 
lodgepole pines extended for a distance of at least 10 to 11 miles 
north of the smelter, 9 to 10 miles south of it, and 10 miles to the west. 
SULPHUR TRIOXID IN FOLIAGE OF TREES AROUND WASHOE 
SMELTER. 
The samples of injured foliage near the smelter and of uninjured 
foliage of the same species of trees beyond the apparent range of 
damage collected on the trips just described were examined for sulphur 
trioxid and ash and the results compared, as in the previous investi- 
gations around Anaconda. Samples of soil beneath the injured and 
uninjured trees were also examined to determine whether or not any 
increase in the sulphur trioxid content of the injured trees might be 
due to a larger amount of this constituent in the soil. The results 
obtained are given in Table XIII, which shows that the soils near the 
smelter contained in nearly al! cases practically the same amount of 
sulphur trioxid as those beyond the range of apparent damage. It 
is not necessary, therefore, to take the soils into consideration in 
comparing the injured with the uninjured trees. 
