Sanitary Chemistry.
117
by the relation mlNlvlp M, /a2N2v2v c a p , the values of LY (electrolytic dissociation) being obtained by the graphical method described by the author in 1896. T h e agreement was found to be fairly satisfactory in the case of mixtures of NaCl and HC1, and of K I and KC1, but less so in the case of BaCl, and HC1. The discordant results with CuSO, and H,SO, were explained on the assumption of the presence of acid salt in the solution. The Magnetic Molecular Susceptibility of Salts of the Iron Group. BY 0 . LIEBKNECHT AND A. P. NILLS. Phys. Rev., IO, 215--228.-The method employed was that described by du Bois, in which a paramagnetic solution is diluted with a diamagnetic solvent until the motion of the meniscus of the resulting mixture in a capillary tube placed in a strong magnetic field became zero. T h e halogen salts, nitrates and sulphates of chromium, manganese, iron, cobalt, nickel, and copper were investigated with the following general results : The molecular susceptibility increases from chromium to manganese and iron, and then decreases to copper. With the halogens there is an increase from the fluoride to chloride, with a following decrease to the iodide. Simple additive properties do not appear to be present. Experiments on the effect of a magnetic field on surface tension as indicated by the dropping ” method confirmed Quincke’s results and conclusions in the case of paramagnetic solutions. In the case of diamagnetic water, the dropping could be completely stopped by a field in which the magnetic force acts upward against the hydrostatic pressure. Unmagnetic solutions dropping in an atmosphere of illuminating gas were uninfluenced by a magnetic field.
SANITARY CHEMISTRY. 13. H. RICHARDS,REVIEWER.
A Study of the Relative Value of Lacmoid, Phenacetolin, and Erythrosine as Indicators in the Determination of the AIkalinity of Water by Hehner’s nethod. BYJOSEPHW. ELLMS. J . A m . Chem. Soc., 21, 359-36g.-The author concludes that all the indicators are suitable with proper care and skill, but that if uniformity of results within very narrow limits is desired the preference should be given to erythrosine. Measurements of 4 ‘ Turbidity ” in Water. BYW. P. MASON. J . A m . Chem SOL.,21, 516-517.-The turbidity of the water is compared with that of a standard kaolin solution ( I gram per liter) in a 2-foot tube and is expressed in parts per million. Standard Methods of Water Analysis. PRELIMINARY REPORT, Comm. A m . Pub.Health Assoc., GEO. W. FULLER, CHAIRMAN. Eng. Record, Oct. 2 7 , 1900 ; Science, 12, 9?6-915 ; Ann. Rept, A m . Pub. Health Assoc., 26, 315-316.-Thelimits ofanab-
118
Review of AnaevicaIi Chcimcal Research.
stract will not permit of any extended notice of the twelve different chemical tests discussed in the report. The Artesian Basins of Wyoming. BY WILBUR C. KXIGHT, 1Vyo. Exjt. Sta. Bull., 45, 1-250.-In connection with a discussion of water-bearing zones the author gives analyses of twentyseven wells and springs from various geological formations in the state. These range from 8 grains per gallon of total solids to I I I 5 grains; from 0.7 to 40 grains CaCO.,;from 0 . 2 to 73 grains IJgSO,: with other ingredients in similar fluctuating proportions. On pages I 82 and I 83 will be found a summary of the character of the water to be expected from seventeen horizons. As usual the purest water is found in the Archean. The Determination of Phosphates in Potable Waters. BY A.G . I T T AKD~ I,. I~,. CAYCXS. ~ ~ 1. ~ A m .~ Cheui. ~ SOL.,23, g6-1o;-.--After a resunie of previous work and a description of the methods used, the authors give with diagrams the results of their study of the effect of teniperature 011 the color developed and on dehydration of silica. A colorimetric method is described which is applicable to colorless well waters but has not yet been made suitable to colored surface waters. Permanent Standards for Use in the Analysis of Water. BY DAKIEL D. JACKSON. Tech. Qziart., 13, 314--326.-The author says that colorimetry plays such an important part in the analysis of water that standards for comparison are in constant use. Much time would be saved if permanent solutions could be kept on hand and the paper is an account of the preparation of six of these standards, uiz.,for color, turbidity, nitrogen as atnmonia! as nitrite, and as nitrate, and for iron. Description of Experimental Filter Plant at Pittsburgh, and Results of Experiments. BY MORRIS KNOWLES.J , N. E. Water 1VorX.s Assoc., 15, 148-188.-After a discussion of the apparatus and methods used eight tables of results of the chemical examination of the water of the Allegheny river and of the effluents of the sand and mechanical filters are given. The following summary of the general results for the seven months ending August 31, 1898 will be of interest. Percentage of constituents removed. Mechanical filters.
.................... ............
Sand filters. ,-----*---. KO.
................. .............. ........ .......... .............
“1
............
-A_---
Warren.
Jemell.
57
IO
88 53 5
3 5 31
3 6 3s
T O . I.
Color 13 Nitrogen as alb. ammonia. 47 Free ammonia IO h-itrites .................... Nitrates. ................. -13 Chlorine 2 Total solids 30 Suspended matter IOO Total hardness * -34 Alkalinity., .45 Sulphuric acid..
2.
73 48
..
..
IO0
-35 -46
..
:9 33 -62
88
IO
.. 8
I2
39 98 IO
31 -38
