B R IT IS H C H E M I C A L A B S T R A C T S
A .-P U R E CHEMISTRY
M A Y , 1932.
G eneral, P h y sica l, and Inorganic C hem istry.
Perturbed series in line spectra. A. G . S h e n - s t o n e and H. N. R u s s e l l (Physical Rev., 1932, [ii], 39, 415—434).—Mathematical. The series in the spectra o f Ca i , Ba i , Hg i , Cu i , and A1 i i are discussed.
N. M. Blight. High-intensity discharges in gases. Z. B a y
(Math. Nat. Anz. Ungar. Akad. Wiss., 1930, 47, 569—585; Chem. Zentr., 1931, ii, 3308).—The spectra of discharges in H 2, N 2, Ne, and N e-H g mixtures were studied. “ A. A. E l d r i d g e .
Fine structure of the 4686 H e+ line in parallel electric and m agnetic fields. D. P. R a y - C h a u d - htjei (Z. Physik, 1932, 74, 711—713).
A. B. D. C a s s i e .
Absorption and resonance of the helium infra
red lines. M. R. W e h r (Physical Rev., 1932, [ii], 39, 796—801).—The absorption and variation of absorption with source tube conditions of He excited at low voltages for its own lines 10,830 and 20,582 A.
Were determined. The 10,830 A. line shows strong resonance directly proportional to the % absorption;
the 20,582 A. line shows very small absorption and
no detectable resonance. N. M. B l t g i i .
Mean free path, excitation probability, and excitation function in sodium vapour. L. S.
O r n s t e i n (Proc. K. Akad. Wetensch. Amsterdam, 1931, 34, 1259—1263).—The excitation probability in Na vapour is calc, from a comparison of the in
tensities of the Hg line 5461 A. and the Na D line. The mean free path is calc, from the diminution of in
tensity with distance from the grid. E. S. H e d g e s .
Influence of inert gases on N a resonance radiation. L. v o n H a m o s (Z. Physik, 1932, 74, 379—-387).—An unsuccessful attempt to obtain emission from excited atoms enhanced by collision m described. Inert gases do not extinguish Na resonance radiation, but merely broaden the lines.
A. B. D. C a s s i e .
f/(/)-Factors for the nuclei of chlorine, phos
phorus, and alum inium . S . Tol a n s k y (Z. Physik, 1932, 74, 336—343).—Line spectra of Cl n, P n , A11, and A1 i i indicate exceptionally small g(/)-factors for the nuclei 27, 31, 35, and 37, suggesting that the magnetic nuclear moment is not determined by proton spin alone. A. B. D. C a s s i e .
Hyperfine structure of resbnance lines of gall
ium. D. A. J a c k s o n (Z. Physik, 1932, 74, 291—
294),-—The nuclear spins of the two isotopes of Ga are either both 3/2 or 0 and an undetermined quantity
(cf. Campbell and Bacher, Physical Rev., 1931, [ii], 38,1906). A. B. D. C a s s i e .
Fine structure of the visible absorption bands of bromine. W. G. B r o w n (Physical Rev., 1932, [ii], 39, 777—787 ; cf. A., 1931, 1344).—Analyses of the group of bands in the main absorption band sys
tem of Br2 79>81, vibrational isotope shift of band origins, and vibrational and rotational consts. are
given. N. M. B l i g h .
Spectrum of strontium hydride. W . W . W a t s o n and W. R. F r e d r i c k s o n (Physical Rev., 1932, [ii], 39, 765—776).—Full data for the three groups of SrH bands in the near infra-red with main heads at 7020, 7347, and 7508 A. are recorded.
N. M. B l i g h .
Mean life of cadm ium atom in states 3Pj and
1
P 1. P. S o l e i l l e t (Compt. rend., 1934, 194, 783—784; cf. A., 1928, 930).—The calc, mean life of the Cd atom in the states 23P1 and 21P1 (2 X10~® sec. and approx. 1 0 -8 sec.) is confirmed experimentally.
C. A. S i l b e r r a d .
Mean lives of atom ic states. H. D. K o e n i g
and A. E l l e t t (Physical Rev., 1932, [ii], 39, 576—
584).—Direct measurements are made by means of the thermal motion of excited atoms in two forms of resonance lamps. The val. 2-5 x lO-6 sec. was found for the 2 3P 1 state of Cd. N. M. B l i g h .
New resonance series in diatom ic tellurium vapour. J. P i é r a r d (Bull. Acad. roy. Belg., 1932, [v], 18, 180—185; cf. A., 1931, 1204).—B^rom the tvro series previously investigated the vibration levels of Te2 are deduced. Term vais, and separations for the 4Ô58 A. series are tabulated, and for a new series excited by the 5005 A . line of N. I t was not possible to separate the 4245 and 4387 A. series.
N. M. B l i g h .
First spark spectrum of cæ sium (Cs II). 0 .
L a p o r t e , G. R. M i l l e r , and R. A. S a w y e r (Physical Rev., 1932, [ii], 39, 458—466; cf. A., 1931, 1204).—
The ultra-violet spectrum was photographed; wave
lengths, classifications, and intensities are tabulated for 87 lines. The ionisation potential of Cs n is
23-4 volts. N. M. B l i g h .
Spectrum of barium hydride. W. R. F r e d r i c k s o n and W. W. W a t s o n (Physical Rev., 1932, [ii], 39, 753—764).—Full data for the BaH band system in the region 6925—6380 A. are recorded.
N . M . Bl i g h.
h h 439
4 4 0 B R I T I S H C H E M IC A L A B S T R A C T S .— A .
Spectrum of doubly-ionised cerium . A. S. K in g and R. B. K in g (Astrophys. J., 1932, 7 5 , 40—45).—
20S lines from 2167 to 3544 Ä. have been measured.
These lines probably belong mainly to doubly- ionised Ce. L. S. T h e o b a l d .
Tem perature classification of the spectra of ytterbium and lutecium . A . S. K i n g (Astrophys.
J., 1931, 7 4 , 328—341).—Details of the electric furnace, arc, and spark spectra between 2950 and 6800 Ä. are given for Yb and Lu. L. S. T h e o b a l d .
F irst spark spectrum o f m ercury. R . R i c a r d
(Compt. rend., 1932,1 9 4 , 781—783).— 49 hitherto un
classed lines of Hg n are tabulated and 18 other lines are classified by the aid of three new terms.
C. A. S lL B E R R A D .
M etastable atom s in m ercury fluorescence.
(L o r d ) R a y l e i g h (Nature, 1932, 1 2 9 , 344).—Experi
ments which prove that both kinds of metastable Hg atoms, 23P 0 and 23P a, are present in the stream of fluorescent vapour excited by the resonance line 2537 A. are described. L. S. T h e o b a ld .
Hyperfine structure of the m ercury resonance line 2 5 3 7 Ä. II. S. M r o z o w s k i (Bull. Acad.
Polonaise, 1931, A, 489—521).—An examination the hyperfine structure of the Hg resonance line, 2537 Ä., showed that the lower I1*?,, level of the Hg atom is not split up. By adding inert gases it was found that three of the components arise from one kind of isotope, whilst the other two components arise from another
isotope. W. R. A n g u s .
W ave-length shifts of certain spectral lines of H g H . A. I m a z a t o (Sei. Rep. Tokyo Bunrika Daigako, 1932, A, 1, 179—192).—The wave-length shifts of lines in the Hg II spectrum at fairly high pressures were studied. A. J. M e e .
Hyperfine structure of the m ercury line
5 4 6 1 A . L. S ib a iy a (Nature, 1932, 1 2 9 , 472).—
A new satellite of the line is recorded.
L. S. T h e o b a l d . H y p e r fin e s t r u c t u r e s a n d n u c le a r m o m e n t s o f m e r c u r y . II. H. S c h ü l e r and E. G. J o n e s (Z. Physik, 1932, 74, 631—646; cf. this vol., 2).—The hyperfine structures of a further 8 Hg n lines suggest a nuclear moment of 1/2 for the isotope 199 and 3/2
for 201. A. B. D. C a ssie .
Effect of nuclear spin on the radiation excited
b y electron im pact. W. G. P e n n e y (Proc. Nat.
Acad. Sei., 1932, 18, 231—237).—A theory of the polarisation of radiation excited by electron impact must take into account nuclear spin. Exact expres
sions are deduced for a few special cases and applied to the particular case of Hg. The anomalous be
haviour of the Hg 2537 A. line is due to the exaggerated importance which electron exchange has in exciting the 2SP X level. J. W. S m i t h .
Intensity m easurem ents in the arc spectrum of thallium . S. E. W i l l i a m s and J. H e r l i h y
(Physical Rev., 1932, [ii], 3 9 , 802—805).
N . M. Bl ig h.
Spectrum of bism uth hydride. E. H u l t h A n
and A. H e i m e r (Nature, 1932, 1 2 9 , 399).—Further details of the band spectrum previously reported (A.,
1931, 664) are recorded and discussed. The band system shows indications of a hyperfine structure due to the high nuclear spin in the Bi atom (cf. this vol.,
104). L. S. T h e o b a l d .
W ave-length determ inations in the higher spark spectra of lead and bism uth in the farthest ultra-violet. G. A r v i d s s o n (Ann. Physik, 1932, [v], 1 2 , 787—819).—The determination of the wave
lengths of the spectral lines of Pb and Bi in the region 1400—200 A. was carried out by means of a vac.
spectrograph and a concave grating, using grazing
incidence. A. J. M e e .
Central intensity in the Fraunhofer lines. A.
P a n n e k o e k (Proc. Iv. Akad. Wetensch. Amsterdam, 1931, 3 4 , 1352— 1364).—Mathematical.
J. W. S m i t h .
Arc, spark, and glow : a note on nomenclature.
J. T h o m s o n (Phil. Mag., 1932, [vii], 1 3 , 824—834).—
Suggestions for rationalisation. H. J. E m e l k u s .
Electrodeless discharges. J. S. T o w n s e n d
(Phil. Mag., 1932, [vii], 1 3 , 745—759).—Theoretical.
H. J. E m e l A u s .
M echanism of the positive colum n in mon- atom ic gases. I. R. S e e l i g e r (Physikal. Z., 1932, 3 3 , 273—294).—A summary of theoretical and practical investigations on this subject.
J. W. S m i t h .
Sim ple m ethod of estim ating the intensity relationships of two neighbouring spectral lines.
H. S t u c k l e n (Ann. Physik, 1932, [v], 1 2 , 701—729).
W. R. A n g u s .
Nuclear spin and hyperfine structure in band spectra. S. M r o z o w s k i (Nature, 1932, 1 2 9 , 399—
400).—A discussion (cf. this vol., 104).
L. S. T h e o b a l d .
Intensities in sin glet-triplet bands of diatomic m olecules. R. S c h l a f p (Physical Rev., 1932, [ii], 3 9 , 806—815).—Theoretical. N. M. B l i g h .
Zeeman effect of qpiadrupole lines a c c o r d i n g
to D irac’s theory. B. M i l i a n c z u k (Z. Physik, 1932, 74, 810—824). A. B. D. C a s s i e .
Transition effects in quadrupole lines. B.
M i l i a n c z u k (Z. Phvsik, 1932, 7 4 , 825—845).
A. B. D. C a s s i e .
D ispersion of light in the region of q u a d r u p o l e
lines. J. B l a t o n (Z. Physik, 1932, 7 4 , 41S—42S).
A. B. D. C a s s i e .
Dynam ical system s of continuous spectra.
B. O. K o o p m a n and J. v o n N e u m a n n (Proc. Nat.
Acad. Sci., 1932, 1 8 , 255—263).—Mathematical.
Theory of widening of spectral lines according to w ave-m echanics. B. M r o w k a (Ann. Physik,
1932, [v], 1 2 , 753—786).
Spectrum of cosm ic radiation. I. Measure
m ents of autum n 1 9 2 8 . E . R e g e n e r (Z. Physik, 1932, 7 4 ,433—454).—Measurements of ionisation due to cosmic radiation at depths down to 230 ni.
in Lake Constance show a homogeneous radiation after absorption by SO m. of H20 ; the absorption coeff. for this radiation is 1-9 X lO-4 per cm. H20, and probably corresponds with the radiation of the mass of a He nucleus. A. B. D. C a s s i e .
Spectrographic observations of infra-red lines in the auroral spectrum . L. V e g a r d (Nature, 1932, 129, 468).—A strong and a weak narrow band have been observed at 7883 and 8095 A ., respectively.
None of the infra-red 0 lines can be identified with these two lines. L. S. T h e o b a l d .
Non-polar auroral ligh t from the night sky in the tropics. K. R. R a m a n a t h a m and J. V.
K a r a n d i k a r (Nature, 1932, 129, 545).
L. S. T h e o b a l d .
Red radiation from oxygen in the night sky.
W l G r o t r i a n (Naturwiss., 1932, 20, 1 82—18 3 ).— A criticism of Sommer’s work ( i b id ., 85).
W. R. Angus.
Peculiar stellar spectra. III. Occurrence of europium in A-type stars. W. W. M o r g a n (Astrophys. J., 1932, 75, 46—59).
L. S. T h e o b a l d .
Spectrum of the corona. S. A. M i t c h e l l (Astrophys. J., 1932, 75, 1—33). L. S. T h e o b a l d .
O r i g i n o f t h e c o r o n a l l i n e s . T . L. d e B r u i n (Nature, 1932, 129, 468— 469).—Unclassified lines are discussed. The green auroral line 5577 A. and the green coronal line 5303 A . have their origin in the same metastable level of the neutral oxygen level JS0 ; thus
“ coronium ” is neutral oxygen. L. S. T h e o b a l d .
M - and AT-series. E. L i n d b e r g (Nova Acta Reg. Soc. Sci. Upsaliensis, 1931, 7, No. 7, 7—74;
Chem. Zentr., 1931, ii, 2833).—if-E m ission spectra of U, Th, Bi, Pb, Tl, Au, Pt, Ir, Os, Re, W, Ta, and Hf were studied; the difference in wave-length for a doublet is approx. const, for different elements. M -
and iY-series lines of Lu, Yb, Er, Ho, Dy, Tb, Gd, Eu, Sm, Nd, Pr, Ce, La, and Ba, and the Af-absorption spectra of U, Th, Bi, Pb, Tl, Hg, Au, Pt, and W were also studied. A . A. E l d r i d g e .
Intensity ratio of fluorescent X-ray lines. G.
v on H e v e s y and E. A l e x a n d e r (Nature, 1932, 129, 315).—The intensity ratio of the Ag Zj32 and L 3 Z lines varies with the effective wave-length; hence, in chemical analysis, when exciting secondary lines with continuous radiation, the same voltage must be applied as is used in the standardisation.
L. S. T h e o b a l d .
Complex X-ray characteristic spectra. M. N.
S a h a , S. B h a r g a v a , and J. B . M u k e r j i (Nature, 1932, 129, 435).—Attention is directed to a third class of characteristic lines, which arc due to double ionisation and double transition. L. S. T h e o b a l d .
Scattering of X-rays by polyatom ic gases.
Y. H. Woo (Physical Rev., 1932, [iij, 39, 555—560).
—The general expression for the intensity of total scattering is modified by substituting the average for the true at. structure factor. Results are in agree
ment with the measurements of Wollan (cf. A., 1931,
781). N. M. B l i g h .
(Scattering of X-rays by polyatom ic g ases.]
O- E. M. Jauncey (Physical Rev., 1932, [ii], 39, 561).
—A note on Woo’s paper (cf. preceding abstract).
N. M. B l i g h . Cross-section for transferen ce of ch arge and ionisation of a rgon b y argon *. F. W o l f (Z.
“hysik, 1932, 7 4 , 575—592). A. B. D. C a s s i e .
Secondary phenom ena that influence the prim ary photo-electric effect of cæ sium atom s adsorbed on salt layers. J. H. d e B o e r and M. C. T e y e s (Z. Physik, 1932, 74, 604— 623).—The sensitivity of photo-electric cathodes can bo consider
ably increased by using thick salt layers with adsorbed Cs, which renders the layer photo-electrically con
ductive; the red wave-length limit can also be extended from 0-9 g for thin layers to 1-2 g for the thick layers. A. B. D. C a s s i e .
Rate of ionisation of the atm osphere. G. R.
W a i t and O. W. T e r r e s o n (Nature, 1932, 1 2 9 ,401—
402). L. S. T h e o b a l d .
Spark potentials in pure gases. Spark poten
tial in pure hydrogen. K. Z u b e r (Ann. Physik, 1932, [v], 12, 665—700).—The representation of the spark potentials by a half-logarithmic method is discussed and compared with the usual methods of representation. Measurements have been made on very pure H2. W. R. A n g u s .
Hydrogen chromosphere. J. W o l t j e r , j u n .
(Nature, 1932, 129, 580).—Theoretical considerations lead to a hypothesis of the convection of H atoms by outward-moving Ca+ atoms in the solar chromosphere.
L. S. T h e o b a l d .
Electron isom erism . R . S c h m i d (Magyar Chem.
Fob, 1931, 37, 157— 163; Chem. Zentr., 1931, ii, 2695).—A discussion of the rôle of electron quantum numbers in atoms and mois. ; differences between para- and dia-magnetic NO are discussed. The equilibrium const, of the change p-NO ri-N0 -f- 343 g.-cal. is dependent on the temp.
A. A. E l d r i d g e .
Dirac's equation and the spin-sp in inter
actions of two electrons. G. B r e i t (Physical Rev., 1932, [ii], 39, 616—624; cf. A ., 1930, 1327).—
Mathematical. N. M. B l i g h .
M agnitudes characteristic of the Dirac electron.
A. P r o c a (Compt. rend., 1932, 194, 836—838).
C. A. S lL B E R R A D .
Two quantum term s of an electron in a two- centred system . G. C. W i c k (Z. Physik, 1932, 74, 773—779). A. B. D. C a s s i e .
Wave equations of an electron in real form . D. M e s k y n (Phil. Mag., 1932, [vii], 13, 834—844).
Eigenfunctions for calculating electronic vibra
tional intensities. P. M. D a v i d s o n (Proc. Roy.
Soc., 1932, A, 135, 459—472).—Mathematical. It is suggested that the Morse formula is valid only under certain conditions, and some new eigenfunctions, useful for the graphical calculation of intensities, are established. Transitions from the fixed vibrational and rotational state of the upper electronic level to states in the lower electronic level differing from each other only in their vibrational quantum no. are considered. L. L. B i r c u m s h a w .
Polarisation of electrons by double scattering.
N. F. M o t t (Proc. Roy. Soc., 1932, A, 135, 429—
4 5 9).—Mathematical. A continuation of previous work (A., 1929, 861) on the application of Dirac’s relativistic theory of the electron to the scattering of electrons by atoms. L. L. B i r c u m s h a w .
4 4 2 B R I T I S H C H E M IC A L A B S T R A C T S .— A .
Electrons, protons, and tlie so-called electron m agnetism . A. G u n t h e r - S c h u l z e (Z. Physik, 1932, 74,692—706).—Theoretical. Electron-magnet- ism appears to be an unnecessary fiction.
A. B . D. C a s s i e .
Excitation of atom ic m ercury by electron im pact. W. G. P e n n e y (Physical Rev., 1932, [ii], 3 9 , 4 6 7 — 4 7 3 ).—Mathematical. N. M. B l i g h .
Precision m ethod for determ ining the therm al diffusivity of solids. R. H. F r a z i e r (Physical Rev., 1932, [ii], 39, 515—524).—Results for N i are accurate to 0*1%. N. M. B l i g h .
M ultiple excitation of com plex atom s by electronic collisions. L. G o l d s t e i n (Compt. rend., 1932, 194, 773—776).—Mathematical.
C. A . S lL B E R R A D .
Angular distribution of slow electrons sca t
tered by gas m olecules. III. C. R a m s a u e r and R. K o l l a t h (Ann. Physik, 1932, [v], 12, 837—848;
cf. A., 1931, 782,1107, 1206).—The method previously described is applied to Kr and Xe, and to these gases mixed with A, using electrons of velocity < 1 volt.
Whilst all the gases behave similarly, there are un
doubted differences at the smallest electron velocities.
A . J. M e e .
N ew determ inations of light production by electronic and ionic collisions. W. H a n l e [with 0 . T h i e m e , G. H a f t , 0 . F i s c h e r , and K. L a r c h e ] (Pliysikal. Z., 1932, 33, 245—247).—Work on the He, Hg, Na, A, and N2 spectra is described.
A. J. M e e .
Inelastic and elastic electron scattering in argon. A. L. H u g h e s and J. H. M c M i l l e n (Physical Rev., 1932, [ii], 3 9 , 585—600).
N. M. B l i g h .
Doppler effects in hydrogen canal rays of uniform energies. H. F. B a t h o a n d A. J. D e m p s t e r (Astrophys. J., 1932, 7 5 , 34—39)
L. S. T h e o b a l d .
Spectroscopic detection of a new isotope of lead. H. S c h u l e r and E. G. J o n e s (Naturwiss., 1932, 2 0 , 171).—A new isotope of Pb (Pb204) has been detected by an examination of the hyperfine structure of the 7228, 5201, and 5005 A. lines of Pb i and the 5609 A. line of Pb n. W. R. A n g u s .
Isotope investigations of hydrogen and helium by m a ss spectrograph. H. K a l l m a n n and W.
L a s a r e v (Naturwiss., 1932, 2 0 , 206).—A spectro
graph method indicates the presence in ionised H of ions of mass 1, 2, and 3. B y another method traces of an ion of mass 4 were found. The intensity ratio of ions of mass 3 to that of ions of mass 2 was found for very low pressures to be 1 :4000. In He an ion of mass 5 was detected in traces. A. J. M e e .
C h o i c e o f b a s i s f o r a t . w t s . S. M e y e r (Pliysikal.
Z., 1932, 33, 301—302).—The val. 16-00000 for the O16 isotope is regarded as the best present standard
for at. wts. J. W. S m i t h .
At. w ts. of selenium and tellurium . H. L.
J o h n s t o n (J. Amer. Chern. Soc., 1932, 54, 824—825).
—Aston’s work on the isotopes of Se and Tc and their relative percentages is discussed.
C. J. W e s t (c).
H ighest atom ic num ber. V. V. N a r l i k e r
(Nature, 1932, 129, 402).—Theoretical considerations for the view that the highest possible at. no. is 92 and not 137 are advanced. L. S. T h e o b a l d .
Radioactivity and theorising. B. W i l l i s (Amer.
J. Sci., 1932, [v], 23, 193—226).—A discussion of the views of Holmes, Joly, Chamberlin, Barrel, and
Adams. C. W. G i b b y .
Fine structure of a-rays of thorium-C. S.
R o s e n b l u m and M. V a l a d a r e s (Compt. rend., 1932, 194, 967—970; cf. A., 1931, 280; this vol., 5 ).- Using an improved method the probable existence in the spectrum of Th-C-fC" of the rays (figures in parentheses denote velocities X 10~9) ar (2*248), alr (2*13j), am (2*14)?, a4 (1*642), and a5 (1*621) is con- firmed. Two new lines (Hp 542 and 660) were measured in the (3-ray spectrum of Th-B-f-C'-f (7 (cf. A., 1925, ii, 922). C. A. S i l b e r r a d .
Com position of atom ic nucleus. W. D.
H a c k h (J. Amer. Chem. Soc., 1932, 54, 8 2 3 -8 2 4 ).- Nuclear structure and the explanation of radioactive loss of a-particles are discussed. Isotopes differ only in the no. of neutrons. C. J. W e s t (c).
Long-range a-particles from Th-C'. J. P o r t
(Z. Physik, 1932, 74, 740—743).—Measurements accurate to 2% were made of the intensity and range of these particles by means of the simple Geiger method (cf. i b id ., 1928, 49, 753). A. B. D. C a s s ie .
M easurem ent of ionic m obility. G. S t e t t e r
(Pliysikal. Z., 1932, 3 3 , 294—296).—The valve electrometer (A., 1929, 737) is applied to the measure
ment of ionic mobility. a-Particles are fired into an ionisation chamber, one wall of which is comiected to a high potential whilst an end-plate and part of one wall are connected to the electrometer. The time is observed between the registration of a deflexion due to the a-particle and of the deflexion due to the discharge of the ions. The results are in good agree
ment with previous vals., but indicate that the mobilities of similar ions are much more uniform than was previously supposed. J. W. S m ith .
a-Radiations of radiothorium , radioactinium, and their derivatives ; com plexity of a-radiation of radioactinium . (M m e .) I. C u r i e (J. Phys.
Radium, 1932, [vii], 3 , 57—72).—The rays from Ra-Ac consist of two groups; the relative formation of Ac-X indicates that the latter is formed by the emission of an a-particle from one of these groups.
The energy difference, 2*8 x lO 5 volts/electron, of the groups is that of one of the groups of y-rays of Ra-Ac, or of the most penetrating y-rays of Ac-X.
N. M. B l i g h .
Ionisation effects of rays from beryllium due to a-rays from radon. M. d e B r o g l i e , F. D. La
T o u r , L . L e p r i n c e - R i n g u e t , and J. T h i b a u d (Compt.
rend., 1932, 194, 1037— 1040; cf. this vol., 443).- The particles produced in an ionisation chamber by the rays resulting from the bombardment of Be with a-rays from Rn are more strongly ionising, although only 1 /2 to 1 ¡3 as numerous, when there is no sheet of paraffin at the entrance to the c h a m b e r .
Their no. and nature seem connected with the vol.
of gas therein, but are unaffected by the material of
the walls or by moisture thereon. A screen of ZnO (7-6 g. per sq. cm.) between the Be and the chamber absorbs about 40% of the radiation; IyN 0 3 and par
affin act similarly. No retrograde emission of protons from paraffin was detected. The no. of particles turned through 0—45° in the ionisation chamber is about 5 times, that of those showing double tracks double, the no. mathematically probable.
C . A . S lL B E R R A D .
(3-Rays of ra d iu m -/). E. S t a h e l (Nature, 1932, 129, 314).—A discussion and a criticism (cf. A., 1931,
1349). L. S. T h e o b a l d .
2-Rays of radium -J). N. F e a t h e r and H. 0 . W.
R i c h a r d s o n (Nature, 1932, 129, 314— 315).—A reply to criticism (cf. preceding abstract).
L. S . T h e o b a l d .
Magnetic spectrum of 3-rays of thorium -li.
S. S h ih - Y u a n (Compt, rend., 1932, 1 9 4 , 874—876).
—By reducing the continuous spectrum by a special arrangement, Hp and intensity for 20 (3-rays (6 doublets) of Th-A have been determined, Hp 1398 being taken as standard (cf. A., 1925, ii, 922). The corresponding levels of origin and y-ray energies are tabulated. C. A. S i l b e r r a d .
Upper lim it of the continuous (3-ray spectrum of Ra-E . K. C. W a n g (Z. Physik,' 1932, 74, 744—
747).—A Geiger-Muller counter gave the upper limit of this spectrum at an Hp val. of 5300.
A. B. D . C a s s i e .
Half-value period of uranium -y . O . G r a t i a s
and C. H. C o l l i e (Proc. Roy. Soc., 1932, A, 135, 299—306).—A redetermination of the half-val. period of U-F leads to the val. 24-0±0-58 hr.
L. L. B i r c u m s h a w .
Passage of neutrons through m atter. H. S . W.
M a s s e y (Nature, 1 9 3 2 , 129, 4 7 0 ).— A theoretical investigation of the interaction of a neutron with an electron. L. S. T h e o b a l d .
Possible existence of a neutron. J. C h a d w i c k
(Nature, 1932, 129, 312).—The radiation emitted when Be is bombarded by a-particles of Po ejects particles from H 2, He, Li, Be, C, air, and A. The particles from H 2 behave like protons with speeds up to approx. 3-2 X109 cm. per see., whilst those from the other elements appear to be recoil atoms of the elements. The results are best explained on the assumption that the radiation from Be is not a quantum radiation, but consists of neutrons or par
ticles of mass 1 and charge 0. L. S. T h e o b a l d .
Ejection of atom s by very penetrating radiation excited in ligh t atom s. (Mme.) I. C u r i e and F.
J o l i o t (Compt. rend., 1932,194, 876—877).—Several photographs of the tracks of protons and He nuclei referred to previously (cf. this vol., 318) are repro
duced, and show that the ejections are not due to the impact of anything that produces an ionising path. " C. A. S i l b e r r a d .
Ejection of light nuclei by very penetrating radiation. Paths photographed by a W ilson chamber. P. A u g e r (Compt. rend., 1932, 1 9 4 , 877—879; cf. this vol., 210, 318).—The effects pro
duced by the penetrating radiation emitted by Be under the influence of Po have been examined in a
Wilson expansion chamber in a strong magnetic field.
With moist air in the chamber electronic tracks arising from the impact of the radiation on the wall were obtained, indicating potentials of up to 6-5 X 10®
volts, due possibly to the Compton effect. With a moist mixture of H 2 and A (3 : 1) the tracks originated in the gas and are due to protons of energies from 50,000 to several million electron-volts, projected at all angles <90°, with no apparent relation between their velocity and the direction of projection. It is suggested that the different effects are due to two types of radiation, one, electromagnetic, causing the Compton effect, the other, the neutrons suggested by Chadwick, which project the protons (see above).
C. A. S i l b e r r a d .
[Ejection of light nuclei by very penetrating radiation.] M. d e B r o g l i e (Compt. rend., 1932, 194, 879—880; cf. preceding abstract).—Similar results have been obtained by bombarding Be with a-particles from Ra, the y-rays being filtered out by a Pb screen. The no. of particles observed by means of an ionisation chamber was trebled when paraffin was placed at the on trance. Similar results were obtained whether the chamber was of Al, Zn, Cu, or Pt. C. A. S i l b e r r a d .
Chemical behaviour of ekatantalum . O.
G r a t i a s and C. H. C o l l i e (J.C.S., 1932, 987—988).—
The protoactinium from about 1 g. of pitchblende, conc. with Ta oxide and placed in the ionisation chamber of a valve amplifier, was estimated by register
ing on a counter the no. of particles emitted. The reactions with fused KOH and K H S04 and with HF were similarly studied and were in agreement with those of Grosse (cf. A., 1930, 883) using relatively large quantities. N. M. B l i g h .
Radioactive disintegration and nuclear spin.
G. G a m o v (Nature, 1932, 129, 470).—The radii of radioactive nuclei have been calc. The spins of such nuclei can also be estimated.
L. S. T h e o b a l d . C h a r t o f a t o m i c s t r u c t u r e . W. D . H a c k h
(Chem. News, 1932, 144, 168— 171).
Number of free protons in the nucleus. A. ,J.
R u t g e r s (Nature, 1932, 129, 361—362).—A dis
cussion of certain difficulties. L. S. T h e o b a l d .
Distribution of elem ents and curve of atom ic volum es. J. J. S a s l a v s k i (Z. anorg. Chem., 1932, 204, 222—224).—Among the first 28 elements the most widely distributed are those which occur at minima in the curve of at. vols. F. L. U s h e r .
Som e periodic properties of atom ic nuclei.
G. I. P o k r o v s k i (J. Amor. Chem. Soc., 1932, 54, 623—625). E. J . R o s e n b a u m (c).
Possible explanation of the difference in m ass of the proton and electron. A. P r o c a (J. Phys.
Radium, 1932, [vii], 3, 83— 101).—By the introduc
tion of a new invariant in the theory of the electro
magnetic field it is shown that the “ rest mass ” of a proton and electron can be expressed as A - j - e B
and A — e B , respectively, where A is a coeff. termed the “ true mass,” which is the same for the proton and electron, and B is a variable term depending
B R I T I S H C H E M IC A L A B S T R A C T S .— A .
o n t h e e le c t r o m a g n e t i c f i e ld c a l l e d i n t o a c t i o n b y a l l m e a s u r e m e n t s o f m a s s . N . M. B l i g h .
Relations between fundam ental physical con
stants. J. E. M i l l s (Science, 1932, 75, 243).—A numerical relation between the velocity of light, on the one hand, and e, Planck’s const., the mass of the electron, the mass of the proton, or other funda
mental const, on the other, has been found.
L. S. Th e o b a l d.
N ew determ ination of e/m from the Zeeman effect. J. S. C a m p b e l l and W. V. H o u s t o n
(Physical Rev., 1932, [ii], 3 9 , 601—615).—The val.
e /m = l-7 5 7 9 ± 0 -0 0 2 5 x l0 7 e.m.u. per g. was obtained from the Zeeman separations of the X 6439 Cd and the
>.6362 Zn lines. N. M. B l i g h .
Ratio of the m asses of the proton and the electron. C . H. D . C l a r k (Naturwiss., 1932, 2 0 ,
182).—The ratio of the masses of the proton and the electron, m„/ m e, maybe written equal to 2 7 4 - ( - —1) by accepting the relationships of Perles and Eddington.
This gives a val. of 1843-5 which is approx. the arithmetic mean of the spectroscopic and “ deflexion ” vals. of the ratio. W. R. A n g u s .
U ltra-violet absorption of am m oniacal solu
tions of inorganic salts. H. F r e d h o l m (Svensk Kern. Tidskr., 1932, 44, 44— 48).—A 0-5N solution of LiCl containing 0-5 equiv. of NH 4C1 and 0-433 equiv. of NII3 per litre shows absorption in the ultra-violet; MgCl2 and CaCl2 show similar effects, which are ascribed to tho formation of complexes, but K, Na, Ba, and Sr have no action. ZnCl2
<0-2AT has absorption in the far ultra-violet. The addition of increasing amounts of NH 3 to the solution diminishes the absorption. CdCl2 in aq. N R , be
haves similarly. The effects with Zn and Cel are probably due to differing absorption of the two complexes of type M(NH3)2 and M(NH3)4; the asymmetric diammine has a strong absorption, whilst the symmetrical tetra-ammine shows less absorption than a solution containing the correspond
ing quantity of free NH3. A similar phenomenon has been observed in the case of the system CuS04+
h N H 3 (cf. A., 1927, 1009). H. E. H a r w o o d .
Sim ple relations between m olecular spectra and structures. II. D e s l a n d r e s (Compt. rend., 1932, 194, 1033—1037; cf. this vol., 211).—An amplification of views previously expressed, with further examples. C. A. S i l b e r r a d ,
Relation between ultra-violet absorption spectra and the velocity of reaction of certain types of am ines. M. G r u n f e l d (Compt. rend., 1932, 1 9 4 , 1083—1085).—The ultra-violet absorption of ?i-amyl-, -octyl-, -dodecyl-, cycZohexyl-, and 2- methylcycZohexyl-amines in EtOH and in hexane, and of their hydrochlorides in H 20 , has been determined.
Those which have the same velocity of reaction with CH2(C02Et)2 (this vol., 371) have the same
absorption. J. W. B a k e r .
Structure of the third positive group of CO bands. G , H. D i e k e and J. W. M a u c h l y (Nature, 1932, 1 2 9 , 546).—The bands 0— >-0 to 0— >-4 with
heads at 2833,2977, 3134,3305, and 3493 A. have been studied. They are due to a 3S— >-3II transition.
L. S. T h e o b a l d .
Certain relations between constitution of dyes and their colour intensity. A. R. P e t e r s o n and W. C. H o l m e s (J. Physical Chem., 1932, 3 6 , 633—
641).—The absorption coeffs. of various dyes were determined in aq. and EtOH solution. The absorp
tive power of the azo-, CHPh3, and quinoneimine dyes is greater in 94% EtOH than in aq. solution. On a mol. basis of comparison, the CHPh3 and pyronine dyes are the most intensely coloured. In a given group of dyes, substitution which increases tho mol.
wt. increases the mol. absorption, but usually reduces the sp. absorption. S. L e n h e r (c).
Infra-red photography. H. W i l l e n b e r g (Z.
Physik, 1932, 7 4 , 663—680).—Local changes in thickness of a thin oil film, due to evaporation by the heat of incident infra-red rays, are detected interfero- metrically. Photographv is thus extended to 6-5 p.
A. B . D . C a s s i e .
Infra-red region of the spectrum . V. Ab
sorption spectrum of carbonyl sulphide.
0
. R.B a i l e y and A. B . D . C a s s i e (Proc. Roy. Soc., 1932, A, 1 3 5 , 375—391).—An analysis of the infra-red absorption spectrum of COS shows that this substance is intermediate in structure to C02 and CS2- The mol.
behaves as though its structural formula were OIOS.
Further evidence in favour of this is adduced from thermochemical data. L. L. B i r c u m s h a w .
Behaviour of the spectrum of w ater in the tem perature interval
20
—220
° and in the spectral range 1—3-2 p. B. S t a n s f e l d (Z. Physik, 1932,7 4 , 460—465).—Comparison of the spectra of H20 at 20° and of II20 vapour at 120° shows that absorption max. for the vapour state occur at lower wave-lengths.
This displacement of the absorption max. is also found when the spectra of H20 at 20° and 97° are compared. The 1-414 p and 1-881 p bands of H„0 vapour are not displaced by raising the temp, to 220°, but there is a slight displacement in the 2-62 p band. Results on Raman spectra of H 20 and its vapour are discussed. The shifts in the absorption max. are probably due to changes in the state of mol.
aggregation. W. R. A n g u s .
Com parison of the rotation-vibration spectra of the liquid and gaseous states of certain organic substances (ethyl alcohol, form ic acid, acetic acid, ether, nitrobenzene). B. S t a n s f e l d (Z. Physik, 1932, 7 4 , 466—475).—The absorption spectra of EtOH, H C02H, AcOH, and E t20 in the liquid and gaseous states have been measured from 1 to 2-7 p ; liquid and gaseous P h N 0 2 have been in
vestigated from 1 to 3-8 p. Some of the bands in these substances appear to be influenced by temp., the absorption max. of the liquid occurring at a longer wave-length than the corresponding max. for the vapour. The spectra are compared with each other.
The displacements of the max. are discussed and a tentative explanation is put forward.
W. R. A n g u s .
M easurem ents in the long wave-length infra
red from 2 0 p to 1 3 5 p . R. B . B a r n e s (P h y sica l
Rev., 1932, [ii], 3 9 , 562—575).—The technique of
the region and the elimination of shorter wave-lengths are discussed. New data for the transmission of fused and cryst. quartz, S, paraffin, mica, celluloid, black paper, cellophane, soot films, Bi-black, and a lamp
black-water-glass prep, are recorded. S showed 8 absorption bands which are compared with Raman effect data (cf. Krishnanmrti, A., 1930, 1237).
N. M. B l i g i i .
Near infra-red absorption spectra of the rare earths. R. F r e y m a n n and S. T a k v o r i a n (Compt.
rend., 1932, 194, 963—964).—The following max. of absorption bands between 0-82 and 1-16 p. were deter
mined with the author’s apparatus (cf. this vol., 6) and solutions of the neutral chlorides of concn.
8N—N/32 (where different the most persistent bands are denoted by an *): Pr 10,182, Nd S660*, S755, 8891; Sm 9508, 10,869*; D y 9090, 11,054; Ho 8930 (weak); Er 9742; Lu (probably) 9400, 9740; none was observed with La, Ce, Eu, Gd, Tb, Y, and Tin.
C. A. S i l b e r r a d .
Infra-red absorption spectra of nuclear hydro
carbons. P. L a m b e r t and J. L e c o m t e (Compt.
rend., 1932, 194, 960—962).—Absorption spectra be
tween 7 p. and 16 p of the following have been deter
mined : cyciohexane and 1 : 3- and 1 : 4-dimethyl- q/clohcxanes (show some resemblances to, but more essential differences from, the corresponding benzenes);
cyciohexene and the three methylcyciohcxenes (show no further approach to the corresponding bpnzenes);
C10H8, 1- and 2-methyl-, 1 : 6- and 2 : 6-dimethyl-, tetra- and deca-hydro-naphthalene (all show a char
acteristic band near 12-8 p. except the last, which differs as cycfohcxanc from CeH 8) ; Ph2 (distinctly different from C6Hg or C10H 8) ; and CH2Ph2 and CHPh3 (show clearly their relation to PhMe). C. A. S i l b e r r a d .
Near infra-red absorption spectra of som e halogen derivatives of m ethane. J. G. M o o r h e a d
(Physical Rev., 1932, [ii], 39, 788—795; cf. this vol., 212; Bennett and Meyer, A., 1929, 239).—The fine structure of 7 bands of MeCl, MeBr, and Mel in the region 1-5—3-0 p. was measured. N. M. B l i g i i .
Molecular rotation of solid sodium nitrate.
J. M. B i j v o e t and J. A. A. K e t e l a a r (J. Amer. Chem.
Soc., 1932, 54, 625—628).—A structural model for NaNOj in agreement with intensities of the lines of the powder diagram is proposed. R. H. L a m b e r t (c).
Structure of Rayleigh radiation. E. H. L.
M e y e r and W. R a m m (Physikal. Z., 1932, 33, 270—
272).—The spectra of C6H 6, PhMe, and CC14 have been investigated with an interference spectroscope. B e
sides the primary lines there are new lines due to splitting. The displacements agree closely with those calc, from a formula due to Gross. The red displace
ment noticed by Cabamies and others is not found.
A. J. M e e .
Atoms and m olecules as Fitzgerald oscillators.
R. Bär (Nature, 1932,129, 505).—With incident light horizontally polarised, the Raman lines of thiophen show complete depolarisation; the anomalous polaris
ation reported by Venkateswaran ( i b i d . , 1931,128,795) does not exist. L. S. T h e o b a l d .
Polarised p hosp h orescen ce lig h t. P . F r ö h l i c h (Math. Nat. Anz. Ungar. Akad. Wiss., 1930, 47, 79—95; Chem. Zentr., 1931, ii, 3305).
Angular distribution of intensity of Ram an lines. D. P. R a y - C h a i t d h t j r i (Z. Physik, 1932, 74, 574; cf. A., 1931, 1353).—A correction; the law of distribution for the 4617 A. line of C6H 6 is different from that of the 4215 and 4555 A. lines.
A. B. D. C a s s i e .
Raman effect and dipole m om ent. A. K a s t l e r
(Compt. rend., 1932, 194, 858—861).—The Raman frequency, Av, is usually less in the liquid than in the gaseous state, rarely, e .g ., in HCN, the reverse.
In general Av is largest where the mols. have a per
manent dipole moment, being due to the influence of the electrostatic fields of neighbouring mols. on the linkings attaching the valency electrons. These being negatively charged and as a rule screening the posi
tive nucleus, the nearer approach of another negative charge weakens the linking and diminishes Av. Where, as in HCN, there is an unscreened H + the effect is the reverse. This agrees with other relations between the Raman effect and constitution (cf. A., 1924, ii, 372; 1930,840; this vol., 7). C. A. S i l b e r r a d .
Polarisation of Ram an scattering. S. B h a g a - v a n t a m and S. V e n k a t e s w a r a n (Nature, 1932, 129, 580).—Improved measurements with many liquids show that no line has a depolarisation > 6 /7 , the limiting val. Certain vibration lines of C6H 6, HC02H, C4H4S, and the tetrachlorides of Sn, C, Si, and Ti show this val., which is also reached in all cases of a rotational scattering whether by gases or liquids.
The 992 cm.-1 line of C8II8 shows 7% depolarisation and the lines 459, 426, 382, and 367 of CC14, SiCl4>
TiCl4, and SnCl4, respectively, show depolarisations of 4, 11, 12, and 16%. The Rayleigh scattering in these tetrachlorides is accompanied by a rotational Raman scattering and is depolarised to an extent which increases with an increase in the at. no. of the central atom. L . S. T h e o b a l d .
Raman effect w ith inorganic com plexes, especially co-ordinated com pounds. I. Damas-
CHUN (Z. physikal. Chem., 1932, B, 16, 81— 101).—A Raman frequency attributable to internal vibration of the complex ion has been observed with aq. solu
tions of some only of the various ammines and com
plex cyanides examined. The intensity of these lines is great enough to indicate that the binding forces in the complex ions are almost non-polar. The Raman lines of the various tungstic and molybdic acids are sufficiently characteristic to serve as a means of identification. Aq. ZnCl2 gives a line traceable to ZnClG"". No line which could be ascribed to the
complex Cu(H20 ) 4" lias been found. R. C u t h i l l .
Influence of sulphur dioxide on the glow of phosphorus. A. B l a h a and F. S c h a c h e r l (Coll.
Czech. Chem. Comm., 1932, 4, 69—71).-—P does not glow in pure S 0 2. Curves representing the influence of poisons on the max. pressure limit of the glow of P are always convex towards the concn. axis if the concns. of the poisons are expressed by the ratio of the partial pressures of the poison and 0 2.
■ E. S. H e d g e s .
D i s c o l o r a t i o n a n d a f t e r - g l o w o f c a r b o n a t e a n d o x i d e p h o s p h o r s . L. W e s c h (Ann. Physik, 1932, [v], 12, 730—742).—The experimental arrangement and the prep, of the phosphors are discussed. The
4 4 6 B R I T I S H C H E M IC A L A B S T R A C T S .— A .
discoloration of carbonate phosphors is not influenced hy the phosphorescence of different metals; in the molten state the phosphor is discoloured. The dis
coloration results from discoloration of the alkali halides. The heavier is the alkali halide the greater is the discoloration. The light emitted by phosphors on irradiation with ultra-violet light or with cathode or high-frequency radiation is considered.
W . R . An g u s.
Detection of /{-absorption constants in phos
phors and a new sensitive m ethod for the spectral analysis of high-frequency radiation.
L. W e s c h (Ann. Physik, 1932, [v], 12, 743—752).—
Several sulphide phosphors have been examined.
W . R. A n g u s .
Elementary processes of chem ilum inescence.
H . B e u t l e r (Angew. Chem., 1 9 3 2 , 45, 2 4 9 — 2 5 4 ) .—
A lecture. E. S. H e d g e s .
Energy transform ations at surfaces. V.
Phosphorescence of adsorbed, fluorescing dyes and its relationship to reversible and irrevers
ible structural changes of gels. H. K a u t s k y
and A. H i r s c h (Ber., 1932, 65, [J3], 401—406; cf.
this vol., 7).—The luminescence of dyes on dry org.
adsorbates (paper, cellojjhane, cotton-wool, artificial silk, ramie, wool, silk, gelatin) does not differ essen
tially from that on inorg. media (loc. c it.) and is best observed on writing paper. The displacement of the bands towards longer wave-length with diminishing temp, is very marked. Dry paper phosphors are not sensitive to 0 2, but become increasingly sensitive with increasing H 20 content. Large amounts of H 20 completely inhibit phosphorescence. The effect of 0 2 can therefore be observed only with papers of low II20 content and is not comparable with its effect on S i0 2 adsorbates. The diminution of intensity and duration of phosphorescence depends on the length of pre-illumination of the phosphor. The bearing of these observations on the structure and ageing of
gels is discussed. H. W r e n .
Cold tem perature radiation. A. G u n t h e r - S c h u l z e and H. B e t z (Z. Physik, 1932, 74, 681—
691).—A temp, can be ascribed to an energy dis
tribution among electrons in an electrolyte; this temp, determines the intensity of light observed at an A1 anode in citric acid, assuming blaok-body conditions.
The temp, and the corresponding intensity of black - body radiation were varied by varying the potential across the cell and verified the assumption of a Maxwell distribution of energy among the electrons.
A. B. D. C a s s i e .
Tem perature crests in cando-lum inescence.
E. L. N i c h o l s and H. L. H o w e s (J. Opt. Soc. Amer., 1932, 22, 170— 189; cf. A., 1927, 7, 607).—Further evidence for the existence of maxima, characteristic of the activator, in the brightness-temp. curves of rare earths in the H flame is given; the brightness greatly exceeds that of a black body at like temp.
The effects of adding an activator, Gd, Nd, Pr, Sm, were investigated. N. M. B l i g h .
M icrographic investigations of the ‘ ‘ cuprous '' rectifier. M, T o r r e s (Z. Physik, 1932,74,770—772).
—Photomicrographs indicate that Cu crystal extends throughout the Cu20 layer. A. B. D. C a s s i e .
Conductivity of silver sulphide. W. Jost (Z.
physikal. Chem., 1932, B, 16, 129—142).—The high vai. for the sp. conductivity, k, of a-Ag2S previously reported (A., 1929, 1369; 1931, 1213) has been verified. In an atm. free from S, and also in presence of S, k is depressed considerably by the formation of mixed crystals with Cu2S. This suggests that the mobility of the Cu ions in these mixed crystals is much less than the mobility of the Ag ions in pure Ag2S, which would account for the fact that the vah of k deduced from the rate of diffusion of Cu ioas into Ag2S is far smaller than the directly determined val. The possible explanations of high ionic mobilities in solid compounds are examined, none being found quite satisfactory. R. C u t h i l l .
Photo-electric properties of cadm ium sul
phide. R. A u d u b e r t and ( M l l e . ) C. S t o e a
(Compt. rend., 1932, 194, 1124— 1126).—A CdS elec
trode is prepared by electrolysing an alkali sulphide with Cd as anode (cf. this vol., 126). The photo
electric effect of the cell Cd|CdS|Na2S,aq.|Cd shows max. for A 5200 A., and 3900 (smaller), and a min.
for 4100 A. Photo-electronic effect, if present, is quite secondary. C. A. S i l b e r r a d .
Photoconductivity of diam onds. ( S i r ) R.
R o b e r t s o n , J. J. Fox, and A. E. M a r t i n (Nature, 1932, 129, 579).—Four more diamonds (cf. A., 1930, 1237) of the type transparent at 8 g and as far as 2300 A. in the ultra-violet region are reported. Most of the diamonds of the transparent character produce a current on illumination without applying a voltage across the diamond; the most effective wave-length is approx. 2300 A. L. S. T h e o b a l d .
Peculiar form of activity of m atter. G.
R e b o u l (Compt. rend., 1932, 194, 1122— 1124; cf.
this vol., 321).—In addition to the relatively intense ionisation in the neighbourhood of a resistance cell there emanates therefrom a gas capable of affecting a photographic plate, of producing relatively feeble ionisation, and of imparting activity to objects it touches. I t is suggested that this gas is not in electrical equilibrium and emits radiation in returning slowly thereto (cf. A., 1931, 405).
C. A. S i l b e r r a d .
Effective radii of com bined atom s, and o r t h o
effect in dipole m om ents. M. M a g a t (Z. physikal.
Chem., 1932, B , 16, 1— 18).—Since Wohl’s data for mol. diameters (A., 1931, 1216) show that space
filling of a mol. is additive, the effective radii of various atoms and groups have been calc, from liquid vols. at 0° abs. and from mol. radii deduced from viscosity data. The results show that in o-disub- stitution products of C6H 6 the dimensions of the substituents are not, in general, great enough for sterie effects to be responsible for the o rth o effect in dipole moments. I t is probable that the effect is primarily due to the influence of directive valency forces on the angle between the linkings by which the substituents are attached, mutual polarisation of the dipoles also playing a part. In o-dinitrobenzene the plane of the N 0 2-groups seems to make an angle, not exceeding 40°, with the plane of the ring. R. C u t h i l l .
Total electric polarisation and the electric m om ents of certain organic m olecules. L. M.
