Mr. Waldie's investigations connected 



[No. 1, 



organic matter present. It was impossible of course to get the hot 

 season water in its original condition, but experiments could be made 

 with river and tank water, and with mixtures intended to imitate the 

 real or supposed peculiarities of hot season water. These could be 

 examined to ascertain the amount of change produced on them by 

 keeping. Accordingly experiments were made the results of which 

 are exhibited in the following table. 



For 100,000 jL grains W. 



Date of collection Date of Esspt. 



Organic matter. 



Oxygen rec 



or preparation. 



Grains. 



Grains. 



Calcutta Sewage 



Water. 





13th Sept. 1866, 13th Sept. 





2.300 



14th 





2.040 



15th 



21.80 





17th 





1.470 



27th 



10.75 





Mixtures of River Watei 



• with Sewage. 





No. 1, containing |th Sewage. 







10 th September. 10th Sept. 



5.44 



.535 



11th 





.480 



15th 





.422 



24th 



3.63 





25th 





.624 



*2nd October, 





.203 



No. 2, containing ^th Sewage. 







11th September. 11th Sept. 





.245 



12th 



2.18 





15th 





.163 



24th 



1.88 





25th 





.441 



*2nd October, 





.353 



No. 3, containing \ Sewage and | Barn. 



Tank Water. 





18th September. 18th Sept. 



6.05 



.420 



26th 



2.65 



.725 



*2nd October. 





1.938 



* Introduced after date of paper. 



