DECEMBER 4, 1913] 
NATURE 
409 
to a power of n+n,, where n, is a constant depending 
on the material of the wire. In the Proceedings for 
1912-13 Prof. W. Peddie carries the investigation of 
the problem a step further by showing how the oscil- 
lations themselves are performed. To do this he 
provides the lower surface of the oscillating’ body 
with a number of pins, which make contact with 
mercury placed in slits in the top surface of an ebonite 
disc. The resulting currents operate the recorders of 
an electrical chronograph. He finds that the period 
of the motion towards, is distinctly greater than that 
away from, the equilibrium position, and that through- 
out the whole of the former and the first part of the 
latter path the motion is of the simple periodic type. 
Both these results, he shows, can be explained on the 
assumption that the motion when it exceeds a certain 
magnitude breaks up molecular groups in the sus- 
pending wire. 4 
An important paper on the phenomena occurring 
in solutions of radio-active products was read by Dr. 
T. Godlewski before the Academy of Sciences at 
Cracow on June 2, and also published in Le Radium 
for August last. In the experiments described a solu- 
tion of radium emanation with its disintegration pro- 
ducts in pure water was electrolysed. Radium A 
appeared at the anode and radium B at the kathode, 
while radium C was deposited in about equal quan- 
tities at both the anode and kathode. The nature of 
this deposition points strongly to the supposition that 
the products are present in the colloidal state and 
not as ions, the radium A forming negative, radium B 
positive, and radium C both negative and positive 
suspensions. This assumption was verified by experi- 
ments on the effect of adding small amounts of 
different electrolytes, such as HCI, NH,OH, AI,(SO,),, 
and K,C,H,O,, which are known to affect the speed 
and direction of transportation of such suspensions. 
For instance, the H ions obtained by adding HC! in 
very small concentration (0-00003 normal) were shown 
to diminish the number of negative suspensions of 
radium A, and increase the number of positive sus- 
pensions of radium B. With further increase in con- 
centration of HCl the radium A atoms begin to appear 
at the kathode. The action of basic ions was also 
shown to be very pronounced, and in the opposite 
direction to that of acids. The assumption that the 
products in neutral solution are present as colloids is 
also supported by recent experiments of Paneth, who 
has shown that polonium can be separated from lead 
by allowing the latter to diffuse through an animal 
membrane. 
Parts 1 and 2 of the Science Reports for 1913 of 
the University of Sendai, Japan, contain a series of 
papers by Prof. Honda and his pupils on the magnetic 
properties of ferro-, para-, and dia-magnetic substances 
and the effects of temperature upon them. For ferro- 
magnetic substances the observations cover the effect 
of temperature on the intersity of magnetisation at 
various fields, the temperature at which magnetic 
changes occur and the heat developed or absorbed 
during the process. A magnetometric method was 
used. Soils were investigated by the torsion balance 
method, the specimen being placed in a magnetic field 
NO. 2301, VOL. 92] 
for which HdH/dx was known. The susceptibilities 
were found to decrease as the temperature rose and 
to reach a value nearly zero between 500° and 600° C. 
They decreased also with increasing magnetic fields. 
Many alloys of antimony, lead, aluminium, zinc, 
tellurium, tin, and bismuth were investigated by the 
same method to test the influence of composition on 
susceptibility. In no case does it appear possible to 
calculate the susceptibility of such alloys from those 
of their constituents, and in almost all cases the 
alloys having their constituents in simple atomic 
proportions display characteristic magnetic proper- 
ties. 
CircutaR No. 42 of the Bureau of Standards, 
Washington, deals with metallographic testing, and 
contains a concise account of the scope of the subject, 
thermal analysis, and microscopic analysis, followed 
by full directions for preparation and forwarding the 
samples. Circular No. 25 of the same bureau con- 
tains general information regarding standard analysed 
samples. Details are given of the precautions taken 
in manufacture to secure pure and homogeneous 
samples. Before the final bottling, samples for 
analysis are removed from the jars and sent, one 
each, to a number of analysts. In general three 
types of analysts are chosen—commercial chemists, 
works chemists, and chemists of the bureau. When 
all the analytical results have been received they are 
inspected, and, if not sufficiently concordant, analysts 
are sometimes requested to repeat the determinations 
without knowing the direction from the mean in 
which their value lies. The standard samples include 
various steels, zinc ore, iron ores, naphthalene and 
sugar for calorimetric standards, benzoic acid, for 
calorimetry and for alkalimetry, and sodium oxalate. 
The prices are moderate, averaging two dollars for 
quantities of 50 to 150 grams. 
Tue Transactions of the American Institute of 
Chemical Engineers (vol. v.) contains a paper by A. S. 
Cushman and H. C. Fuller, of the Institute of Indus- 
trial Research, Washington, upon a chemical investi- 
gation of Asiatic rice. So far as the results of 
analysis can be interpreted in the light of the informa- 
tion at hand, the authors conclude that there appears 
to be no reason why the white milled rices from one 
section of the world should be held more responsible 
for malnutrition than similar rices from other parts. 
In the same volume J. C. Olsen and A. E. Ratner 
contribute a paper upon the decomposition of linseed 
oil during drying. While oxygen is absorbed, water 
and carbon dioxide are given off, the effect upon the 
weight of the oil being shown. The opacity and hiding 
power of pigments forms the subject of investiga- 
tion by Mr. G. W. Thompson. For the purposes of 
these experiments an apparatus was devised consist- 
ing of a photometer which brings two fields of light 
into juxtaposition, so that they can be compared by 
the eye. This photometer is placed on top of two 
tubes, the lower ends of which have lenses. Paint 
placed between one set of lenses can be compared with 
a standard paint or with pieces of paper which have 
been tested on a photometer bench. Mr. M. C. 
Whitaker contributes a paper on the chemical 
