Nature, 
_ August et. | 
Title Index 
Ivii 

Sierra Leone, Petrographic Survey of, Dr. F. Dixey, 410 
Sikhs of the Punjab, The, 234 
Silent Zone in Explosion Sound-Areas, The, Dr. C. Davison, 
117 
Silica: in Sedimentary Rocks, Deposition of, H. B. 
Manfe ; T. B. Lawler, 412; in Water, Estimation of, 
F. Diénert and F. Wandenbulcke, 831 ; Vitreous, The 
Hardness of, C. Johns and Prof. C. H. Desch, 15 
Silicon, Trebly-ionised, The Series Spectrum of (Si IV), 
Prof. A. Fowler, 689 
Silkworm, Diseases in, Dr. A. P. Jameson, 411 
Sillimanite, Natural, as a Glass Refractory, S. English, 830 
Silver Sulphate, The Dissociation of, Mlle. G. Marchal, 275 
Sioux Tribe, Early History of the, Dr. J. R. Swanton, 480 
Sky-types, Forecasting, D. E. Row, 35 
Slag mistaken for a Meteorite at Quetta, G. H. Tipper, 704 
Sl Movements and Vegetative Reproduction in Plants, 
. T. Saxton; R. H. Dastur, 823 
Sleeping Sickness, Cure of, Dr. A. Balfour, 339 
Smell: and Specific Gravity, J. H. Kenneth, 151; Taste, 
and Allied Senses in the Vertebrates, Prof. G. H. 
Parker, 629 
Smokes, Pt. I., R. Whytlaw-Gray, J. B. Speakman, and 
J. H. P. Campbell; Pt. II., R. Whytlaw-Gray and 
J. B. Speakman, 169 
Snail, Pond, The Name of the, F. A. B., 150 
Soaring Flight and the ‘Olfactory’’ Organs of Birds, 
Lt.-Col. W. E. M‘Kechnie, 48 
Social Question, The New, Capt. J. W. Petavel, 688 
Société Frangaise de Physique, the, 783 
Society, The Psychology of, M. Ginsberg, 145 
Sociology, Biological Contributions to, Prof. J. A. Thom- 
son, 300 
Sodammonium, The Action of, on Aniline and its Homo- 
logues, M. Picon, 35 
Sodium: Hypochlorite, The Catalytic Decomposition of, 
by Cobalt Peroxide, O. R. Howell, 866; Metaphos- 
hate, The Preparation of, at a Low Temperature, 
. Pascal, 795 
Soil: Acidity and Plant Distribution, C. Olsen, 791 ; 
Bacteria : and Organic Antiseptics, P. H. Gray, 893 ; 
The Destruction of Aromatic Antiseptics by, H. G. 
Thornton, 347; Partial Sterilisation of, Sir John 
Russell, 347; Reaction, Water Snails, and Liver 
Flukes, Dr. W. R. G. Atkins and M. V. Lebour, 83 ; 
C. L. Walton, 117; -types, Mineral Constitution of, 
Prof. J. Hendrick and G. Newlands, 786 
Soiling System, devotion, by E. D. Simon, of a farm and 
dairy herd to test, 126 
Sol, Study of the Reversible, to get Transition in Non- 
liqueous Systems, Pts. I. and II., E. W. J. Mardles, 170 
Solanaceous Plants, Some Causes of Sterility in, due to 
Protozoa and Chytridiaceous Parasites, M.S.G. Breeze, 
866 
Solar: Apex, Position of the, J. S. Paraskevopoulos, 159 ; 
Eclipse Investigations, Prof. A. D. Ross, 510 ; Eclipses, 
Coming, 60; Prominence Activity, 27; Radiation, 
Prof. C. G. Abbot and others, 414 
Solids and Liquids, Calorific Capacity of, The Principle of 
a General Method for determining the, C. Moureu, 
C. Dufraisse, and P. Landrieu, 867 
Solution: of Oxygen by Water, Irregularities in the Rate 
of, H. G. Becker and E. F. Pearson, 487; The Law of, 
P. Mondain-Monval, 275; Variation of Heats of, 
with Temperature, P. Mondain-Monval, 554 
Sorby, Henry Clifton, The Services of, to Metallurgy, Prof. 
C. H. Desch, 478 
South Africa: Astronomical Society of, 717 ; Botanical 
Society of, 680; Citrus Fruit from, Miss Thomson, 
Putterill and Hobson, 234; medal and grant, award 
of the, to Dr. I. B. Pole Evans, 162 ; Post-Cretaceous 
Climates of, Dr. A. W. Rogers, 162 ; Recent Volcanic 
Activity in, Dr. P. A. Wagner, 235; Royal Society 
of, election of officers, 613: Union of, Fisheries and 
Marine Biological Survey, Reports for 1920 and 1921, 
Dr. J. D. F. Gilchrist, 270 
South African: Association, The Lourengo Marques Meet- 
ing of the, 162: Fisheries, Exploitation of, Prof. J. S. 
Gardiner, 270; Institution of Engineers, The Central 
Mining-Rand Mines Premium awarded by the, to 
W. J. Horne, 439 

Southampton, University College, G. Grant appointed 
Registrar, 586 
South-eastern Union of Scientific Societies, Annual Con- 
gress of the,*860 
Southport, Meteorological Observations at, J. Baxendell, 
341 
Space: Groups and Crystal Structure, R. W. G. Wyckoff, 
444; The Finitistic Theory of, Dr. Petronievics, 
Dr. N. M. Poppovich, 161 
Spahlinger Treatment of Tuberculosis, The, Dr. L. Williams, 
453 
Spark : -gaps in which the Spark in a Gaseous Dielectric 
is deflected by a Strong Air Current, J. L. Breton, 
383 ; Spectra of Higher Order, L. and E. Bloch, 520 
Specific Gravity Determinations, A Graphical Method of 
correcting, Dr. A. Hutchinson, 486 
Spectra : associated with Carbon, Prof. T. R. Merton and 
R. C. Johnson, 622; Induction, and Spark Spectra, 
L. Dunoyer, 588; The Theory of, and Atomic Con- 
stitution: Three Essays, Prof. N. Bohr, 523 
Spectrometry, Use of the Triode Valve in, L. Bellingham, 
534 
Spectrum, The Disappearing Gap in the, Prof. O. W. 
Richardson, 118, 153 
Speech : Sounds, Nature and Reproduction of, Sir Richard 
Paget, 21 ; The Transmission of, by Light, Prof. A. O. 
Rankine, 744 
Spermatogenesis of the Lepidoptera, H. G. Cannon, 670 
Sphere, Free Motion of a, in a Rotating Liquid at Right 
Angles to the Axis of Rotation, S. F. Grace, 866 
Spiders of New Caledonia, The Origin of the, L. Berland, 
904 
Spiral Nebule: Gravitation and Light Pressure in, Sir 
Oliver J. Lodge, 702 ; Nature of the, Prof. Lindemann, 
615 
Spivanthes Autumnalis, Prof. F. O. Bower, 185 ; 
Smith, J. B. Simpson, 291 
Spirit : Photographs, The Case against, C. V. Patrick and 
W. W. Smith, 139; The Supremacy of, C. A. 
Richardson, 45; concerning the Review of, C. A. 
Richardson, 128 
Spiritualistic «‘ Phenomena "’: Cold Light on, An Experi- 
ment with the Crewe Circle, H. Price, 139 
Spitsbergen : Mites and Rotifers from, 268; the Oxford 
University Expedition to, Lichens collected by, V. S. 
Summerhayes, 309 
Spleen: The, Bolt and Heeres, 339; Prof. C. Richet, 655, 
903 ; Korenchevsky, 893 
Sprengel Pump, A Further Improvement in the, J. J. 
Manley, 242 
Squalodonts, New, from the Miocene of Maryland, R. 
Kellogg, 824 
Stainless Steel, Hardening, Automatic and Electric Fur- 
naces, Ltd., 824 
Standard Air, Laws of Variation of the Characteristics of, 
with Altitude, R. Soreau, 275 
Stane Street: The Topography of, a Critical Review of 
“ The Stane Street,’’ by Hilaire Belloc, Capt. W. A. 
Grant, 630 
Star: Maxima and Minima, Variable, for 1923, Dr. L. 
Campbell, 94; The Interior of a, Prof. A. S. Edding- 
ton (May 12), Suppt. v 
Stark Effect, Easy Method of observing the, Prof. H. 
Nagaoka and Y. Sugiura, 431 
Stars: A-type, Spectroscopic Parallaxes of, Adams and 
Joy, 128; Double: Colours and Spectra of, F. C. 
Leonard, 892; Interferometer Measures of, P. W. 
Merrill, 27; of Type N, The Radial Motions of, 
J. H. Moore, 301 ; Occultations of, by the Moon, 128 ; 
O-type, Spectra of Three, Dr. H. H. Plaskett, 580; 
Parallaxes of Fifty, 94; Radial Velocities of 1013 ; 
W.S. Adams and A. H. Joy, 892; Visual Double, The 
Spectra of, F. C. Leonard, 338 
Steam Power Plant Auxiliaries and Accessories, T. Croft, 
BoP: 
215 
Steatopygous Figures found in France, Dr. R. de Saint- 
Périer, 786 
Steel: Extra Soft, Tempering, at a very High Tempera- 
ture, M. Sauvageot and H. Delmas, 691 ; Properties 
of, Effect of Temperature on Some of the, A. Mallock, 
346; Stainless, with Some Consideration of its 
