824 
average value of this E. M. F. cannot exceed 4 
of a volt. The paper also described experi- 
ments to determine the conductivity of the arc 
after the circuit was broken. The conductivity 
was found to depend upon the direction in 
which current was sent through the arc, and 
the results seem to indicate something in the 
nature of acounter BE. M. F., whose value is less 
than one volt. 
Professor A. G. Webster showed a method 
by which the Maxwell top might be used to in- 
dicate the path of the invariable axis in a body 
moving under the influence of no forces. A 
second paper by Professor Webster described 
quantitative experiments with a top. The 
traces obtained from the top under various 
known conditions were found to agree satisfac" 
torily with the predictions of theory. 
A paper by Professor BE. L. Nichols on the 
‘Efficiency of the Acetylene Flame’ gave the 
results of experiments on this subject since the 
presentation of Professor Nichols’ previous 
paper in June. The values obtained at that 
time have been only slightly modified by the 
later work. 
A paper on the ‘Specific Heats of Elec- 
trolytes,’ by Professor W. F. Magie, gave a 
formula for computing the specific heat in 
the case of solutions in which electrolytic dis- 
sociation occurs. A comparison with experi- 
mentally determined values showed an ex- 
tremely satisfactory agreement. 
A paper by Mr. J. W. Miller, on the ‘ Elastic 
Properties of Helical Springs,’ describing nu- 
merous experiments on this subject, completed 
the program. 
ERNEST MERRITT. 
CHEMICAL SOCIETY OF WASHINGTON. 
THE 126th regular meeting was held April 
11th, when the following program was pre- 
sented : 
‘A New Method for the Estimation of Cane 
Sugar, in presence of Lactose,’ by L. M. Tol- 
man. Benzolsulphinide was used as the hydro- 
lyzing agent, because it has no action on the 
rotation of lactose, even after heating for 
several hours, while a solution of sucrose is 
completely inverted in 80 minutes, by use of 
one-half gram of the sulphinide. The results 
SCIENCE. 
[N. S. Vou. XIII. No. 334. 
obtained showed that it was a satisfactory and 
accurate method. The method used in con- 
densed milk was as follows: Twice the normal 
weight of the milk was weighed into a 200-cc. 
flask and 10 cc. of a 10-per-cent. solution of 
citric acid added to coagulate the casein. The 
liquor was then filtered, 75 cc. of the filtrate 
measured into a 100-cc. flask, one half gram of 
saccharine added and, after shaking, in order to 
break up the lumps, immersed in a boiling 
water bath for 30 minutes. Two ce. of acid 
mercuric nitrate were then added, the solution 
made up to volume, filtered and polarized at as 
near 20° C. as possible. The direct reading 
was taken in the ordinary way and the volume 
of precipitate corrected for by double dilution. 
The results obtained were very satisfactory. 
‘Classification of Alkali Soils,’ by Frank K. 
Cameron. The views presented in this paper 
may be summarized as follows: (1) A classifi- 
cation as black alkali or white alkali, depend- 
ing upon the presence or absence of sodium 
carbonate, is inadequate in view of our present 
knowledge of alkali phenomena. A more com- 
prehensive classification is desirable. Such a 
classification appears to be possible on chemical 
grounds, considering alkali conditions as the 
result of the action of aqueous solutions of cer- 
tain soluble salts upon less soluble salts. (2) 
The action of sodium chloride solutions upon 
gypsum is the predominating feature in certain 
areas and seems to be well typified by the con- 
ditions in the valley of the Pecos in New 
Mexico. The solubility of the gypsum is ap- 
parently much increased by the presence of the 
sodium chloride due to the formation of the 
soluble salts, sodium sulphate and calcium 
chloride. In such an area practically the only 
salts which will have to be considered in the 
ground solutions are sodium chloride and 
sodium sulphate, as well as calcium sulphate. 
Calcium chloride is sometimes found concen- 
trated to a considerable extent, but usually in 
localized and generally small spots. Owing to its 
keeping the soil of these spots moister and, there- 
fore, darker than the surrounding soils, such 
spots are locally known as black alkali spots. 
(8) The action of solutions of sodium chloride 
upon calcium carbonate is the predominat- 
ing feature of some areas. The region about 
