40 The Water Supphj of Minneapolis — Committee. 



a. Water above City contained nitrogen as present in nitrates 



and nitrites ^[jjj parts per million. 

 h. Water at new in-take contained nitrogen as present in nitrates 



and nitrites ^^JIj parts per million. (To the advantage of the 



water above. 



4. The test for organic matter with peyiminganate solution, 



(Tidy's process ) : — 

 a. Water above City required for oxidation of the organic matter 



1 Jj) parts oxygen per million. 

 h. AVater at new in-take required for oxidation of the organic 



matter 2j^ parts oxygen per million. (To the advantage of 



the water above. ) 



5. Determination of the total solid residue from evaporation: — 

 a. Water above City yielded 205 parts per million. 



h. Water at new in-take yielded 205 parts per million. (No ap- 

 preciable difference in this respect.) 



These results of chemical analysis do not show any very con- 

 siderable difference in the two samples of water. But what dif- 

 ference there is in the figures is, in case of each test, to the ad- 

 vantage of the water taken above the City. The water opposite 

 Twenty-fourth avenue north is conclusively shown to be better 

 than that at the new in-take, on the 12th of February. If at this 

 point the question be raised as to the absolute goodness of the 

 waters in question, apart from their relative qualities, it is to be 

 said that, so far as chemical tests r/o^ neither of these samples 

 would be classed among bad waters. Neither of them betrays to 

 the tests of the chemist, a dangerous or even a very objectionable 

 character. The chemical examination of water alone is not suffi- 

 cient to settle its absolute character. Other modes of examina- 

 tion and other considerations of various kinds must hav3 their 

 place. But before passing on to these, we will first make reference 

 to another question which we have settled at the Chemical Lal)- 

 oratory. On the 2d of March two samples of the river water were 

 procured, one at the point where the water is at present taken into 

 the pump-house to be supplied to the mains, the other at the new 

 in-take pipe at the crib above mentioned. These two samples 

 have been analyzed like the others. The several tests have shown 

 a difference between the two samples to the advantage of the new 

 in-take, although the difference is not very considerable. The 

 water at the new in-take was conclusively shown to be better than 



