228 



NA TURE 



[August i i, 1923 



Experiments on two groups of tubes of suspensions 

 show that the rate of fall of the layer boundaries is 

 independent of the temperature gradient within wide 

 limits, and the position of the layers is a function of 

 concentration, time of settling, and thermal gradient. 

 — E. H. Hall: The quasi-equation P=T<iV/iiT. If 

 two plates of dissimilar metals are connected through 

 wires made of the same metals, the plates show 

 opposite charges. If unit charge is made to pass 

 from the positive to the negative plate, heat is 

 absorbed ; this includes the Peltier effect at the 

 junction. Assuming a mass-law of equilibrium 

 between the ions and electrons of the metals, heat- 

 energy is absorbed at the free surface of the metals 

 in addition. This added to the Peltier effect gives 

 nearer accordance with experimental results. — E. F. 

 Nichols and J. D. Tear : Joining the infra-red and 

 electric wave spectra. A Hertzian doublet with 

 minute platinum cylinders acted as the source of the 

 waves. The receiver consisted of a Nichols radiometer 

 in which the vanes were mica strips carrying thin 

 deposits of bright platinum. A new form of reflecting 

 echelon analyser was used for the wave-length 

 measurements. By these means electric waves of 

 lengths varying from 7 mm. to 0-220 mm. were 

 produced and detected, thus overlapping previous 

 measurements for infra-red radiation {e.g. Rubens and 

 Von Baeyer, 0-320 mm.). 



(Proc. Vol. 9, No. 7, July). — A. E. Kennelly : 

 On the constant ratio of mean - to - mid potential 

 or current at successive equidistant points along 

 a uniform electric conducting line, real or arti- 

 ficial, in the steady state. The theorem also 

 applies to tables of hyperbolic sine or cosine 

 functions where the angle increases in uniform 

 arithmetical progression, and to tables of e^*^^ where Q 

 increases in uniform arithmetical progression. — R. 

 Brown : Some recent measurements of transatlantic 

 radio transmission. A high -power vacuum tube 

 transmitter with an output of 2oo'-30o amperes of 

 57,000 cycle alternating current is used at Rocky 

 Point, Long Island, producing continuous radiation 

 of about 5250 metres wave-length. A receiver in 

 London evaluates the absolute root mean square of 

 the electric field produced. The field rises sharply 

 to a maximum during the period when the route is in 

 darkness, but does not exceed the value calculated 

 from the Austin-Cohen radio-transmission formula. 

 Good night transmission seems to be due to a diminu- 

 tion of losses by absorption rather than to focussing 

 effects. — C. B. Davenport : Body build and its 

 inheritance. The ratio, chest girth to stature, or 

 alternatively weight to stature, was used as an index of 

 build in man. A solid figure generated by combining 

 the variability curves with developmental curves shows 

 two main ridges, indicating two main types, medium 

 build and fleshy ; the latter seems to refer to the 

 progeny of fleshy and slender strains, showing 

 dominance of fleshiness. — G. C. Evans : A Bohr- 

 Langmuir transformation. Mathematically, Lang- 

 muir's completely static atom can apparently be 

 shown to be equivalent to the Bohr atom with a 

 circular orbit. — G. A. Miller : Form of the number of 

 the subgroups of a prime power number. — G. Breit : 

 (i) The interference of light and the quantum theory'. 

 Assuming that radiation momenta are transferred in 

 quanta, expressions are derived which represent the 

 effect of (a) a diffraction grating of infinite width, (6) 

 a finite number of narrow, parallel, co-planar and 

 equal slits, and (c) a slit of finite width. (2) Note on 

 the width of spectral lines due to collision and quan- 

 tum theory. The amounts of the broadening appear 

 to be nearly equal to those given on the wave theory 



NO. 2806, VOL. 112] 



of light and can be accounted for similarly. — P. A. 

 Ross : Change in wave-length by scattering. Experi- 

 ments were made to detect the change in frequency 

 of X-rays and 7-rays on scattering by paraffin, 

 aluminium, and graphite suspected by Compton. 

 Relevant equations indicate that the change of wave- 

 length is independent of the primary wave-length. 

 No such shift was observed by scattering the green 

 mercury line at 180° from paraffin. Using photo- 

 graphic methods and X-rays, the reauired displace- 

 ment (about 0-025 •'^•) was observed by scattering 

 the o, and a.^ lines from calcite at 90° from paraffin. 

 Another unshifted line was recorded. — E. L. Nichols : 

 Notes on germanium oxide. The powdered oxide was 

 heated, side by side with a uranium oxide surface, in an 

 oxyhydrogen flame. The radiation of uranium oxide 

 being practically equivalent to black-body radiation, 

 a comparison of the two gives approximately the 

 radiation of germanium oxide in terms of black-body 

 radiation. Preponderance of blue at lower tempera- 

 tures and of red near fusing point are the character- 

 istics. The reversal point is 1225"^ C. and melting point 

 1400° C. — C. Wissler : The correlation of respiratory 

 and circulatory data for adult males. Pulse rates 

 in men before and after exercise show a high cor- 

 relation ( +0-73) ; pulse rate correlates with respira- 

 tion rate ( +0-45) but not with blood pressure and 

 chest mobility. Breathing rate and chest mobiUty 

 appear to be complementary (correlation -0-46), i.e. 

 a man with a mobile chest automatically breathes 

 deeply. — T. W. Vaughan : Studies of the larger 

 tertiary foraminifera from tropical and subtropical 

 America. There appears to be no evidence of de- 

 posits of Lower Cretaceous age at relatively shallow 

 depths in Florida. Deposits of middle and upper 

 Oligocene age occur in northern Colombia. An 

 evolutionary sequence from ancient Eocene forms 

 of Lepidocyclina with meridional chambers, pointed 

 inner ends, and curved outer walls, to species with 

 hexagonal and rhomboid chambers, is suggested. — 

 S. O. Mast : Mechanics of locomotion in Amoeba. 

 Three regions are differentiated in Amoeba proteus: 



(a) a central elongated fluid portion (plasmasol) ; 



[b] a granular layer surrounding the fluid (plasmagel), 

 and [c) a thin elastic surface membrane (plasma- 

 lemma) ; {b) and (c) are semipermeable and (a) is 

 hypertonic. Local swelling of the plasmagel occurs 

 at the tip of pseudopodia with liquefaction on the 

 inner surface at the posterior end. Gelation of 

 plasmasol occurs at the outer posterior border of the 

 swelling. Thus a forward flow is produced which is 

 translated into motion by the adhesion of the plasma- 

 lemma to the substratum. 



Official Publications Received. 



Western Australia. Annual Progress Report of the Geological Survey 

 for the Year 1922. Pp. 12. (Perth : F. W. Simpson.) 



Department of the Interior: Bureau of Education. Bulletin, 1922, 

 No. 42 : Analytic Survey of State Courses of Study for Rural Elementary 

 Schools. ByProf. Charles M. Reinoehl. Pp. v+116. 20cent,s. Bulletin, 

 1923, No. 1 : Diagno.sis and Treatment of young School Failures. By 

 Helen Thompson Woolley and Elizabeth Ferris. Pp. vi+H5. 10 cents. 

 Bulletin, 1923, No. 18 : Medical Education, 1920-1922. By Dr. N. P. 

 Colwell. Pp. 17. .5 cents. (Washington: Government Printing Office.) 



University of Cambridge : Solar Physics Observatory. Tenth Annual 

 Report of the Director of the Solar Physics Observatory to the Solar 

 Physics Committee, April 1, 1922-March 31, 1923. Pp. 8. (Cambridge.) 



Department of Commerce: Technologic Papers of the Bureau of 

 Standards. No. 237 : Aeronautic Instruments. By Franklin L. Hunt. 

 Pp. 447-511. (Washington: Oovemmeut Printing Office.) 20 cents. 



Journal and Proceedings of the Asiatic Society of Bengal. New Series, 

 Vol. 18, 1922. No. 6: Proceedings of the Ninth Indian Science Congress. 

 Pp. xi+197. (Calcutta : Asiatic Society.) 13 units. 



The Rockefeller Foundation. A Re\-iew for 1922 : a Summary for the 

 First Decade. By Geoi^e E. Vincent. Pp. 59. (New York.) 



