OF WATER FOR ORGANIC MATTER. 



73 





Time. 



Oxygen per 

 required 



100 gallons 

 to oxidize 



Oxygen per cent, by weight 

 required to oxidize 



I. 



The de- 

 composed 

 organic 

 matter. 



II. 



The easily 

 decomposa- 

 ble organic 

 matter. 



I. 



The decom- 

 posed organic 

 matter. 



II. 



The easily 



decomposable 



organic 



matter. 



Head of Holy Loch 



Middle of Holy Loch ... 



Dunoon (several loo yds. 

 'from shore) 



Aug. I, '66. 



2.45 p.m. 



2.30 „ 

 July 31, '66. 



I p.m. 



Aug. 16, '66. 



I p.m. 

 Aug. 20, '66. 



1 



12 noon. 

 Aug. 16, '66, 



1-8 p.m. 



1. 15 » 

 Aug. 9, '66. 



12 noon. 



4.30 p.m. 



070 

 0*52 



070 

 070 

 070 



0*52 

 0-35 



0-875 

 0-70 



1-05 

 0-875 



1-57 

 1-05 



I '22 



I '22 



0-875 



0*70 

 0*52 



1-05 

 0-875 



1*22 



1-22 



O'OGOOIO 

 0-0000075 



O'OCOOIO 

 O'OOOOIO 

 O'OOOOIO 



0*0000075 

 0*000005 



0*0000125 



O'OOOOIO 



0-000015 

 0-0000125 



0*0000225 

 0-0000150 



0*0000175 

 0*0000175 

 0*0000125 



o-ooooio 

 0-0000075 



0*000015 

 0-0000125 



0*0000175 

 0-0000175 



Dunoon (about 800 yds. 

 from shore) 



OffDunoon 



Stream at West Bay, 

 Dunoon 



Stream between Innellan 

 and Dunoon 



Between Innellan and 

 Dunoon 



Off Innellan 



Off Wemyss Bay (high 

 tide) 



Off Wemyss Bay (low 

 tide) 





used to assist the oxidation. I suppose this to represent 

 the amount easily decomposed. 



"The 3rd column represents the amount of oxygen 

 used by the organic matter in twenty-four hours. I do 

 not at present see its use. I do not think this at all a 

 fair mode of representing the impurity of water, unless we 

 are sure that the quality does not change. We see this 

 by the numbers above, and at, Glasgow bridge. The purer 

 water has, by this mode of representing it, the appearance 

 of being equal to the worst. The only column that gives 

 the continuous increase and decrease, exactly as the senses 

 find the case to be, is the column No. i. 



" It is not, however, meant that the gases of decom- 

 position are the only evils to be apprehended from impure 

 water; but, so far as I know, they are those that affect 



