638 
NATURE 
[AuGuUsST 5, 1915 

of electrometer, and obtain an instrument theoretically 
sensitive enough to detect 10-°® volts (though un- 
steadiness makes it as yet impossible to detect an 
isolated potential-difference of less than 3 x 10-5 volts). 
—C. Wissler: The distribution and functions of tribal 
societies among the plains Indians: a preliminary 
report. Field-work conducted by the writer and his 
associates in the American Museum of Natural History 
leads to the conclusion that the societies have spread 
from tribe to tribe by culture diffusion of a desultory 
kind; that certain features of organisation are trace- 
able to particular tribes, and no one tribe can be the 
originator of the society system as a whole.—T. W. 
Richards and L. B. Coombs: The determination of 
surface tension. Attention is directed to various 
sources of error in the measurement and in the cal- 
culation of surface tension by the capillary-tube 
method, an improved form of this method is described, 
a new correction for the meniscus is proposed, and 
exact measurements with a number of liquids are 
presented.—Ales Hrdlicka: An exhibit in physical 
anthropology. The exhibits prepared under the direc- 
tion of the author for the Exposition at San Diego 
are described briefly to indicate their breadth, their 
permanent value, and their capability of forming the 
foundation of an anthropological centre.—T. W. 
Richards : The compressibilities of the elements and 
their relations to other properties. This paper records 
all the recent work on the compressibility of the 
elements performed at Harvard, reduced to the best 
available standard—the newly-determined compressi- 
bility of mercury. It is pointed out that the recipro- 
cals of the melting points are very closely associated 
with the coefficients of expansion, and that both 
these properties seem to be essentially connected with 
atomic volume and compressibiljty.—E. B. frost: 
Radial velocities within the great nebulaof Orion. We 
must alter our conceptions of the nebula as an enor- 
mous mass of quiescent gas, and regard it as seeth- 
ing with local whirlpools, besides perhaps having a 
considerable motion of rotation as a whole.—W. S. 
Adams: The radial velocities of the more distant stars. 
The radial velocity of stars increases rapidly with the 
proper motion, and only very gradually with the 
spectral type. This agrees with Eddington’s hypo- 
thesis that the relation between velocity “and spectral 
type may be a relation between velocity and distance.— 
T. H. Morgan: Localisation of the hereditary material 
in the germ-cells. The chromosomes not only furnish 
a mechanistic explanation of Mendelian heredity, but 
in the case of non-disjunction and in the case of the 
point by point correspondence between the linkage 
groups and the chromosomes, furnish a verifiable ex- 
planation of the results. In the case of crossing-over 
and of interference the chromosomes give us the only 
objective explanation of the results that has been as 
yet offered.—G. P. Merrill : Researches on the chemical 
and mineralogical composition of meteorites. Abstract 
of extensive investigations which will appear as a 
memoir in the series of Memoirs of the National 
Academy.—W. B. Ford: The representation of arbi- 
trary functions by definite integrals. The function 
f(x) is represented as the limit of a definite integral 
depending on a parameter when the parameter be- 
comes infinite, or by a series of definite integrals.— 
J. B. Murphy and J. J. Morton: The lymphocyte as a 
factor in natural and induced resistance to transplanted 
cancer. A marked increase in the circulating” lympho- 
cytes occurs after cancer inoculation in mice with 
either a natural or induced immunity. When this 
lymphoid reaction is prevented by a previous destruc- 
tion of the lymphoid tissue with X-ray the immune 
states are destroyed; hence the lymphocyte is a neces- 
sary factor in cancer immunity.—W. D. MacMillan : 
NO. 2388, VoL. 95] 

} 
Some theorems connected with irrational numbers. 
The presence of the factors i—jy in the denominators 
of series rising in celestial mechanics does not affect 
the domain of convergence of the series, provided y 
is a positive irrational number which satisfies a rather 
mild condition. 
BOOKS RECEIVED. 
Descriptive Geometry. By H. W. Miller. Third 
edition. Pp. 149. (New York: J. Wiley and Sons, 
Inc.; London: Chapman and Hall, Ltd.) 6s. 6d. net. 

Fighting the Fly Peril. By C. F. Plowman and 
W. F. Dearden. Pp. 127. (London: T. Fisher 
Unwin, Ltd.) 1s. net. 
Fungoid Diseases of Farm and Garden Crops. 
Dr. T. Milburn. Pp. xi+118. (London: 
and Co,) 2s. net. 
Alcoholometric Tables. By Sir E. Thorpe. Pp. 
xiv+g1. (London: Longmans and Co.) 3s. 6d. net. 
British Museum (Natural History). British Ant- 
arctic (Terra Nova) Expedition, 1910. Natural History 
Report. Zoology. Vol. ii., No. 5. Nemertinea. By 
H. A. Baylis. Pp. 113-134+2 plates. (London: 
Longmans and Co,, and others.) 2s. 6d. 
Catalogue of the Mesozoic Plants in the British 
Museum (Natural History). Part vi. The Cretaceous 
By 
Longmans 

Flora. Part ii. Lower Greensand (Aptian) Plants of 
Britain. By Dr. Marie C. Stopes. Pp. xxxvi+360+ 
Xxxii plates. (London: Longmans and Co., and 
others.) 21s. 
CONTENTS. PAGE 
A Chapter of British Science. By E.R. ....- 611 
hes Principle of Relativity 7.0 see eee 612 
he, Development of Man) 2 ee-uea0neaee 613 
Mathematical ahaa By L. J Ss. ee (ety 
Our Bookshelf Pak ay oud"e gon BORG 
Letters to the Editor:— 
Palzolithic Man in South Africa. (Z//ustrated.)\— 
F. W. Fitzsimons; Prof. Arthur Keith, F.R.S. 615 
Surface Tension and Ferment Action.—Dr, HoraceT, 
Brown, Fo RIS:) see 616 
The Cancer Problem and Radio- activity. eas * at on 
Ross; Prof. J. Joly, F.R.S. . . 617 
The Magnetic Storm of June 17 and Solar Disturbances. 
—Rev. A. L. CortieiS2]5e eee enne 618 
Science and Food- Supply. —AlexanderGrahamBell 618 
The Promotion of Research by the State . 619 
Modern Processes of Manufacturing Hydrogen for 
Airships) 2... 2 «3-3 2 ee eee ee eee 620 
Science, Museums, ‘and the Press . . 621 
Exploration i in the Karakorum. By T. H. D. 10, 622 
Notes Se Or OOee Dro tO soo c 622 
Our Astronomical. Column: — 
An Association for the Observation of Mars ... . 628 
The} Pole Effect in the ironArclsss))- een eee 628 
her Harvard! Observatoryaee ssn een 628 
Annual Review of Astronomy (1914) 2 ate eee 628 
Marine Biology at Plymouth. By E,W. M. ... 629 
The Tapping of Rubber Trees. By H. W.. c 629 
On Beauty, Design, and Purpose in the Fora- 
minifera. (J///ustrated.) By Edward Heron-Allen 630 
Geography of British Fisheries. (JZ//ustrated.) . . . 634 
University and Educational Intelligence ..... 636 
Societies and Academies ee Pees Ce nO 637 
Books Received 638 


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