1867.] 



and the Cholera. 



321 



Quality of the Waters supplied to the Metropolis during the Months of 

 February and April, 1867. 



1. 



Names of Companies. 



2. 



Total solid 



Impurity 



in 100,000 parts 



of Water. 



3. 



Organic 

 Carbon. 



4. 



Nitrogen as 



Nitrates 

 and Nitrites 



5. 



Ammonia. 



6. 



Previous 

 Sewage 

 Contamina- 

 tion. 





Feb. 



April. 



Feb. 1 April. 



Feb. 



April. 



Feb. 



April. 



Feb. 



April. 



Thames. 



Chelsea 



West Middlesex . . . 

 Souttawark and Vauxhall 

 Grand Junction . . . 

 Lambeth ..... 



Other Sources. 



New River .... 

 East London .... 



Kent 



South Essex .... 



28-58 

 28-68 

 29-08 

 29-44 

 29-36 



29-72 

 33 56 

 39-84 

 38-32 



27 86 



28 06 

 28-52 

 28-20 

 28-68 



26-44 

 27-82 

 40- 12 



•433 

 •340 

 •293 

 •417 

 •423 



•272 

 •293 

 •088 

 •143 



•267 

 ■224 

 •166 

 •218 

 •164 



•273 

 •382 

 •131 



•337 

 •356 

 •357 

 •322 

 •341 



•350 

 •357 

 •421 

 •844 



•267 

 •269 

 •298 

 •248 

 •290 



•274 

 •264 

 •409 



•004 

 •006 

 •005 

 •004 

 •005 



•003 

 •004 

 •008 

 •007 



•002 ! 2420 

 •004 2630 

 002 ' 2630 

 •004 2270 

 •004 2470 



•002 ! 2540 

 •010 : 2620 

 •002 3300 

 — 7520 



2195 

 2245 

 1945 

 2115 

 2635 



3155 



2295 

 2155 



Water from Loch | 

 Katrine as supplied in > 

 Glasgow J 



3-28 1 — 



•256 



~ 



•031 



- 



•002 



— j o 



- 



This table is to be read in the following manner : — 100,000 lbs. 

 of the Chelsea Company's water contained in the month of February 

 last 28 ■ 58 lbs. of solid impurity : the organic matter constituting 

 a portion of this impurity contained • 433 lb. of carbon. This 

 solid impurity also contained * 337 lb. of nitrogen in the form of 

 nitrates and nitrites, besides 0'004 lb. of ammonia. The above 

 quantity of water as supplied by the Chelsea Company had been, 

 after its descent to the earth as rain, contaminated with sewage or 

 the manure of cultivated land equivalent to 2,420 lbs. of average 

 London sewage. By gradual oxidation, partly in the pores in the 

 soil, partly in the Thames and its tributaries, and partly in the 

 reservoirs, niters, and conduits of the Chelsea Water Company, this 

 sewage contamination had been entirely converted into compara- 

 tively innocuous inorganic compounds before its delivery to 

 consumers. 



A glance at the table shows how vastly superior is the quality 

 of the water of Loch Katrine as compared with that of the best at 

 present supplied to London. 100,000 lbs. of this water contain but 

 3*28 lbs. of solid impurity, of which only 0*031 lb. is nitrogen in 

 the form of nitrates and nitrites, and 0'002 lb. of ammonia. 

 Further, Loch Katrine water exhibits no sewage contamination, 

 either previous or present. 



The nitrogenous organic matter which has escaped the process 

 of oxidation above described, and which therefore still exists in the 

 water at the time the analysis is made, constitutes what may be 

 appropriately termed the present sewage contamination of the water. 



