492 Scientijie Intelligence. 
someness or unwholesomeness of a drinking water by the mere 
use of any of the processes examined for the estimation of organic 
matter or its constituents, 
(2.) In judging the sanitary character of a water not only must 
such processes be used in connection with the investigation of 
ce 
importance in weighing the reasons for accepting or hci | a 
water not manifestly unfit for drinking on other groun 
3.) There are no sound grounds on which to establish such 
general “ standards of purity” as have been proposed looking to 
exact amounts of organic carbon or nitro i « albuminoid- 
ia,” oxygen of per seagate consumed, et¢., as permissi- 
ble or not. Distinctions drawn by set ‘pplication of such 
oye ds are arbitrary and may te mislea 
Two entirely Homi —- seem to be open for the 
nsf  ecuotci by chemical means of the organic constituents 
of drinking water, namely: ‘first, the ipextie of very gross pol- 
tution; aa as the contamination of the water of a well by 
accidental bursting or crushing of soil-pipes, leakage of drains, 
ete.; and secondly, the periodical examination of a water supply, 
as of a great city, in order that, the normal or oe character o 
the water having been previously ascertained, any suspiciou 
changes which from t time to time may occur, shall be aay 
detected and their cause investigate ed. 
(5.) In connection with this latter application of water analysis 
there seems to be no objection to the establishment of /ocal 
“standards of purity ” for drinking water, based on sufficiently 
thorough examination of the water supply in its usual condition. 
(6.) The facts of this investigation tend to show that special 
and very great sor ay should be attached to a careful deter 
mination of the nitrites and nitrates in water to be used for 
drinking. No aspect in which the good and bad natural waters 
n 
only of the use of simple means of investigation, the albu uminol 
ammonia and permanganate processes te be ps “0 
* ~ metho 
glect of 
carbon on Het ne hand or nitrogen on the other 
mong the more interesting special conclusions reached may 
be quoted the following: 
(1. apt proof has been obtained that in the “ yeorsrl 
proc there = two se meea ee errors, varying 
n amount, namely: loss of ¢ wht? perce tHe 
evaporation of the: water, and gain a nitrogen fro nie 
the atmosphere surrounding the gas flame, the latter r proba y 
oe 
28 » 
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go 
