1870.] Air-pollution by Chemical Works. - 335 



cannot have injured the land ; perhaps it was his friend of the 

 neighbouring works, whose processes are different from his own. 

 Doubtless this gentleman would be equally clear and conclusive 

 in his explanations, and would pass our farmer on once more, to be 

 sent in turn from one to the other, but to get redress from none. 



The farmer soon learns that the only way in which he can 

 obtain compensation from any of the chemical manufacturers is to 

 fix on one of the works, perhaps the one nearest his land, or the 

 one with the highest chimney, and to watch till he thinks he can 

 distinguish the smoke from it come upon his farm. On that he 

 fixes, and, shutting his eyes to the other works and forgetting the 

 injury they probably do him, charges the proprietor with the whole 

 of the damage he has sustained. The judges and juries before 

 whom such cases come for trial are in great difficulty, they know 

 that the manufacturer in question has not done all the damage 

 alleged, yet they have no power of apportioning it between him and 

 other offenders, therefore, as some of the damage has been proved 

 to come from the defendant's works they give a verdict for the 

 plaintiff. 



Among chemical works, the largest, and those capable of doing 

 most harm to vegetation, are the alkali-works. In these works 

 soda, in its various forms of ash, carbonate, bicarbonate, crystal or 

 caustic, is extracted from common salt. Common salt consists of 

 soda in combination with muriatic acid. When it is mixed with 

 sulphuric acid and heated, muriatic acid is driven off as a gas. In 

 the earlier days of the soda manufacture this acid was considered as 

 a waste product to be got rid of as speedily as possible. The easiest 

 way was to let it pass into the chimney and thence into the sur- 

 rounding atmosphere. Complaints were soon made that trees in 

 the neighbourhood were injured. The manufacturer therefore 

 raised his chimney, building it so high that the acid might be carried 

 away to a great distance by the wind and its effects lost sight of. 

 The result of this effort was not successful ; on wet days the rain 

 passing through the smoke would wash down the acid and fall in 

 burning drops even at the foot of the chimney ; while on fine days 

 the smoke would travel farther and though much spread out, still 

 powerful for evil, would carry on its destruction over a larger 

 area. A wiser plan was next adopted ; by the use of the now famous 

 Gossage condensing towers the acid vapours were washed out of 

 the smoke and kept from contaminating the air altogether. Those 

 alkali manufacturers who carried out this method well sent out 

 scarcely any acid vapour to damage the farmers' crops. Some of 

 the manufacturers, however, were behindhand in the movement, 

 and either from want of skill or of enterprise, did not condense 

 their acid vapours. Of the efficiency of this condensation in indi- 

 vidual cases the farmer could not judge ; he found that his crops 



