October 11, 1907] 



SCIENCE 



All 



simultaneously over a large area, if by a large 

 area is understood the country around the 

 smelter for from five to twenty miles, depend- 

 ing upon the direction of the prevailing winds. 

 Again, it has been the writer's experience that 

 successive crops in a given locality did show 

 the effect of smelter fumes. This is especially 

 shown in the vicinity of Ducktown, Tenn., 

 •where the same deciduous trees surrounding 

 the smelter are injured each year until they 

 finally succumb. 



On page 953, Professor Ebaugh also gives a 

 table showing the amount of sulphur dioxide 

 per million parts of air found in the atmos- 

 phere in the vicinity of the smelters in the 

 Salt Lake Valley and in his discussion of this 

 table ends it by saying, " Nevertheless, the 

 very small amount of sulphur dioxide found is 

 certainly surprising." The force of this last 

 sentence is to lead one who knows nothing 

 about the matter to believe that such amounts 

 as were foimd are insignificant and would not 

 be injurious. Let us look at the figures of 524 

 cases examined. In 213 cases, or 40.66 per 

 cent., the amount of sulphur dioxide is one 

 part per million, or more, of the air. By 

 actual experiments of careful workers' it has 

 been shown that plants are injured by repeated 

 treatments of one part sulphur dioxide per 

 million parts of air. Again, as explained by 

 Professor Ebavigh himself, such results as were 

 obtained in the above table are practically 

 valueless since the concentration of sulphur 

 dioxide might be, say, one to 1,000, for a short 

 while and hence do serious injury, while if this 

 amount were spread over an average time of 

 twelve to twenty-four hours, it would amount 

 to a very little. 



On page 954, Professor Ebaugh with the 

 following data: (a) size* of stacks, (6) sulphur 

 dioxide content of stack gases, (c) width and 

 thickness of the visible smoke column at a 

 given time and place, calculates roughly what 

 the sulphur dioxide content of the atmosphere 

 would amount to. The writer is unable to see 

 with the above data how such a calculation 

 could be made with even rough accuracy. 



' See HasellioflF and Lindau's work on " Injury 

 to Vegetation by Fumes." 



Even if such calculation could be made, how- 

 ever, the results are valueless in judging what 

 the sulphur dioxide content of the atmosphere 

 might be at varying distances from the 

 smelter, since on some days and when the 

 fumes float in certain directions, as up ravines, 

 etc., the sulphur dioxide content of the atmos- 

 phere of these ravines might be ten times that 

 of a point on the level country much nearer 

 the smelter and yet in both cases the three 

 factors above' be practically the same. 



On page 956, Professor Ebaugh says : 



Concerning paragraph 5, it should be noted that 

 in the open country one seldom finds sulphur 

 dioxide acting for a long-continued time in one 

 place, etc. 



The writer has in some of the regions which 

 he has visited seen the smelter smoke act on 

 the same side of a mountain range and on the 

 same plants for days at a time and has been 

 told by competent parties residing in the 

 country, that this action in the same direction 

 often continued for weeks. 



On pages 957 and 958, Professor Ebaugh 

 gives his data in regard to the injurious effect 

 of sulphur dioxide on foliage. Note that in 

 every case but one (where one part sulphur 

 dioxide to 50,000 parts of air were used and 

 twelve fumigations on sugar beets) injurious 

 results were noted. Even with the above data, 

 which at the best were not conclusive, because 

 more fumigations should have been used on 

 the sugar beets not injured by twelve fumiga- 

 tions. Professor Ebaugh draws the following 

 conclusion on page 969 : 



By no means is sulphur dioxide to be consid- 

 ered as harmless, especially in an enclosed space 

 and in a moist climate, but we are forced by the 

 weight of the evidence to the conclusion stated in 

 the introduction, viz., that heretofore undue em- 

 phasis has been laid upon the injurious effect of 

 sulphur dioxide upon growing plants, and that 

 the harmful action of the solid emanations from 

 the smelters — the so-called flue dust — has been 

 seriously underestimated. 



The writer is absolutely unable to see that 

 the weight of evidence points in the direction 

 indicated by the above quotation. Judging by 

 the results on fumigation with sulphur dioxide 

 carried out by him in conjunction with the 



