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evaporate 1.000 e. c. is tedious and inconvenient ; 100 c. c. should be 
evaporated in a platinum basin and a good balance is necessary. 
Very few natural waters will fail to give upon the evaporation of 
1.000 c. c. a residue that does not blacken. For nitrates, the delicate 
and inconvenient diphenvlamin test will probably exclude most 
natural waters, even the high-class spring and river waters of this 
region [Philadelphia]. The limits for sulphates and chlorides seem 
to be chosen with more regard to uniformity in the reading matter 
than in the standards. * * * Boiling is not needed, and it is 
especially out of place in the case of the test for chlorides. * * * 
Decanting will suffice instead of filtering. The limits allowed for 
sulphates and chlorides do not seem coordinated nor based on the 
study of analytic data. The extremely delicate napthylamin test 
for nitrites is troublesome in application. Xo caution is given to the 
liability to error from the common occurrence of nitrite in the air 
and dust, nor is it pointed out that deep waters will often give 
marked reactions for nitrates and yet be unobjectionable. In fact, 
the whole water rubric indicates that its authors are unaware that 
the standards of purity in water are correlated with the class to 
which the water belongs. The tests for ammonium compounds and 
oxidizable organic matter are also under the same spell. — Am. J. 
Pharm., Phila., 1906, v. 78, p. 83. 
Coblentz, Virgil, says that a bacteriological examination is more 
to be relied upon than chemical tests, for the exclusion of sewage 
contamination from Aqua U. S. P. Since it is the chief object of 
the pharmacopoeia to exclude such waters as are grossly contam- 
inated. the revised tests will, in careful hands, accomplish this ob- 
ject. — Ibid ., v. 78, p. 393. 
Grosse-Bohle, H., discusses the examination of water and the de- 
termination of its purity. He points out that in addition to local 
inspection it is necessary to utilize the chemical bacteriologic and 
biologic methods. — Ztsclir. f. Unters. d. Xahr. u. Genussm., 1906, v. 
12, pp. 53-60. 
Wyeth, John A., calls attention to the fact that water alone may 
be used as a local anaesthetic after the manner of Schleich method. — 
X. York M. J.. 1906, v. 83, p. 29. 
AQUA DISTILLATA. 
The Ph. Austr. VIII directs that distilled water only is to be 
used in the making of pharmacopoeial preparations and in applying 
the required tests. — Ph. Austr. VIII. p. XXIV. 
The Pharmacopoeia of Japan directs that in every article, where 
properties or tests are described, “ water * always means u distilled 
water.” — Ph. Japon. III. p. XXII. 
