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more severe. I shall be asked here, How do you account 

 for finding fish near the mouth of a sewer ? I dare say 

 they will be found at the mouth of a sewer with a small 

 volume of sewage, but I should like to see them at the 

 mouth of the main sewer from one of our large manufac- 

 turing towns. Perhaps they visit the sewer to pick up the 

 particles of human food brought down by the sewer, or 

 perhaps they are lazy fish, too idle to hunt for their food 

 in a legitimate way, so come to the sewer to imbibe a kind 

 of sewer tipple, instead of food, which sooner or later affects 

 their health, and then they regret the over-indulged in 

 excrementious stimulant, that has undermined their con- 

 stitutions. But the end is the same, I presume, with these 

 dipsomaniac fish, as it is with all the higher species — 



" The ruling passion, be it what it will — 

 The ruling passion conquers reason still." 



But I shall be asked, " How do you account for your 

 assertion that fish cannot long exist in water containing 

 large quantities of sewage ? " It is a well-known fact that 

 fish life is not supported by the oxygen existing in com- 

 bination with hydrogen existing in the water itself The 

 oxygen they breathe is the free oxygen which has been 

 dissolved in the water. Let a fish be placed in previously 

 boiled water, in a stoppered bottle un agitated, and it will 

 soon be found dead. This proves that they require this 

 free oxygen for their existence. By analysis, it has been 

 proved that in sewage-polluted water the quantity of 

 oxygen is much reduced, when a comparison is made 

 with an analysis of unpolluted water. 



The oxygen, in fact, has been consumed in the changes it 

 has undergone, which nothing but time or aeration by agita- 



