
of the fishes in acidified solutions: the nature of 
the acid has also an important influence.—Aug. 
Michel: Caudal regeneration in Polygordius nea- 
politanus.—H. Barthélémy: The maturation in vitro 
and the activation by puncture of the ova of Rana 
fusca at the moment of discharge from the frog.— 
M. Charcot: Preliminary report on the voyages of 
the Pourquoi-Pas? in 1922.—A. Desgrez and H. 
Bierry : A mode of action of Vichy waters. 
WASHINGTON. 
National Academy of Sciences (Proc. Vol. 8, No. 
11, November 1922).—J. A. Marshall: Bactericidal 
properties of the products of radium emanation. 
Old radium emanation tubes which have undergone 
disintegration in respect of y-ray content are crushed 
under Ringer’s solution in a sterile mortar. The 
radioactive solution obtained is conveyed immediately 
to the infected areas by sterile dressings; in the 
case of abscesses at the roots of teeth, it is injected 
through the pulp canal. This treatment gives better 
results than other antiseptic agents.—H. S. Washing- 
ton: The jades of Middle America. The jades 
investigated are from a sacred natural well in the 
ancient Maya city of Chichen Itza, in northern 
Yucatan. The dominant colours are grey and green. 
They are jadeite jades of American origin, and differ 
from Asiatic jadeite in the large amount of diopside 
in the pyroxene they contain and the presence of 
much albite. Analyses are given.—Carl Barus: On 
a comparison of the relative sensitiveness of tele- 
phones. An interferometer U-gauge is connected by 
a quill tube to the telephone mouthpiece and a 
relation is obtained between the fringe movements 
and the constants of the instrument.—Carl Barus: 
The equilibrium positions of the vacuum gravitation 
needle in 1921 and 1922. From the curves given, 
the variations of the position of equilibrium in the 
lapse of time are of a different order in 1922 from their 
approximate constancy, in the given scale, in 1921. 
This may be due to the difference in the vacua 
obtained. All observations have a period of 24 
hours, indicating solar radiation as the origin of 
the variations—W. W. Coblenz: Further measure- 
ments of stellar temperatures and planetary radiation. 
(See NaTuRE, December 30, p. 886.) H. A. Lorentz: 
Proof of a theorem due to Heaviside. The theorem 
in question is: ‘‘The whole work done by impressed 
forces suddenly started exceeds the «amount re- 
presenting the waste by Joule-heating at the final 
rate (when there is any), supposed to start at once, 
by twice the excess of the electric over the magnetic 
energy of the steady field set up.”—A. J. Lotka: 
The stability of the normal age distribution. There 
is an age distribution which, in certain circumstances, 
perpetuates itself when once set up in a population. 
An analytical method is used to show that this 
distribution is stable and that a population spontane- 
ously reverts to it if the age distribution be displaced. 

Official Publications Received. 
Journal of the Indian Institute of Science. Vol. 5, Part 4: In- 
duction Motors used as Synchronous Machines, By S. V. Ganapati 
and R. G. Parikh. Pp. 37-46+9 plates. 1.8 rupees. Vol. 5, Part 5: 
The Relation between the Iodine Values and Refractive Indices of 
some hardened Vegetable Oils. By J. J. Sudborough, H. E. Watson, 
and D. Y. Athawale. Part 1. Pp. 47-69+3 plates. 1.8 rupees. 
(Madras : Indian Institute of Science.) 
Imperial Department of Agriculture for the West Indies. Report 
on the Agricultural Department, Dominica, 1921-22. Pp. iv+382. 
(Barbados.) 6d. 
The British Mycological Society. Transactions. Vol. 8, Parts 1 
and 2, December. Pp. 111. (London: Cambridge University 
Press.) 15s. net. 
Leeds University. Eighteenth Report, 1921-22. Pp. 190. (Leeds.) 
Ministére de |’Instruction publique et des Beaux-Arts. Enquétes 
et documents relatif sa l’enseignement supérieur. 117: Rapports 
sur les observatoires astronomiques de Province. Année 1921. Pp, 
127. (Paris: Imprimerie Nationale.) 
NO. 2775, VOL. I11| 
NATURE 

[JANuary 6, 1923 

Diary of Societies. ‘ 
SATURDAY, JANUARY 6. 
ASSOCIATION OF WOMEN SCIENCE TEACHERS (at University College)» 
at 2.30.—Dr. Dorothy Wrinch: Relativity. 
ROYAL INSTITUTION OF GREAT BRITAIN, at 3.—Prof. H. H. Turner: 
Six Steps up the Ladder to the Stars (5). Two Great Streams of 
Stars (Juvenile Lectures). 
GILBERT WHITE FELLOWSHIP (at 6 Queen Square, W.C.1), at 3.— 
G. J. B. Fox : A Visit to Pompeii. 
MONDAY, JANUARY 8. 
INSTITUTION OF ELECTRICAL ENGINEERS (Informal Meeting), at 7.— 
E. W. Moss, and others: Discussion on the Protection of Inventions 
by Letters Patent. 
ARISTOTELIAN SOCIETY (at University of London Club, 21 Gower Street), 
at 8.—Rev. Leslie J. Walker: A New Theory of Matter. 
SURVEYORS’ INSTITUTION, at 8.—F. W. Hunt: Zoning in the Control 
of Large Cities. 
. 
TUESDAY, JANUARY 9. 
ROYAL INSTITUTION OF GREAT BRITAIN, at 3.—Prof. H. H. Turner: 
Six Steps up the Ladder to the Stars (6). The Size of a Star. 
(Juvenile Lectures.) : 
SOCIETY FOR THE STUDY OF INEBRIETY (at Medical Society of London), 
at 4.—Dr. H. Campbell and others: Discussion on The Pathology 
and Treatment of Morphia Addiction. f 
INSTITUTION OF PBTROLEUM TECHNOLOGISTS (at Royal Society of Arts), 
at 5.30.—Dr. W. R. Ormandy and E. C. Craven: Further Investiga- 
tions into the Physico-Chemical Significance of Flash-Point Tem- 
peratures. 
MINERALOGICAL Society (at Geological Society), at 5.30.—A. Brammall 
and H. F. Harwood: Dartmoor Granite: (a) Rutile, Brookite, 
and Anatase: Genesis. (b) Varieties of Zircon: their significance.— 
Dr. A. Hutchinson: A Graphical Method of Correcting Specific 
Gravity Determinations —Dr. L. J. Spencer, with microscopical 
determinations by W. Campbell Smith, and chemical analyses by 
E. D. Mountain: A Davyne-like Mineral and its Pseudomorphs 
from St. John’s Island, Egypt. F 
INSTITUTION OF CIVIL ENGINEERS, at 6.—H. W. H. Richards: Twelve 
Years’ Operation of Electric Traction on the London, Brighton, 
and South Coast Railway. 
INSTITUTE OF MARINE ENGINEERS, INC., at 6.30.—H. Campbell: Gas 
Engines, and Gas Producer Plants. - 
ROYAL PHOTOGRAPHIC SOCIETY OF GREAT BRITAIN (Scientific and 
Technical Group), at_7.—H. W. Greenwood: The Manufacture of 
Paper for Photographic Purposes. Historical—Hand-made Paper 
—Machine-made Paper—Raw Materials—Preparation—Beating— 
Sizing—Making—Finishing and Baryta Coating. Faults of Manufac- 
ture and their Effect on Emulsions—Testing for Faults, Impurities, etc. 
QUEKETT MICROSCOPICAL CLUB, at 7.30.—Various Members: Notes 
on Mounting. 
CIRCLE OF SCIENTIFIC, TECHNICAL, AND TRADE JOURNALISTS (at 
Institute of Journalists), at 8.15.—Sir Richard Gregory and others: 
Discussion on Reviews and Reviewers. 
WEDNESDAY, January 10. 
ROYAL SOcIETY OF ARTS, at 3.—C. R. Darling: The Spectrum, its 
Colours, Lines, and Invisible Parts, and some of its Industrial ‘Applica- 
tions (Dr. Mann Juvenile Lectures (2)). ; 
GEOLOGICAL SOCIETY OF LONDON, at 5.30. 
INSTITUTION OF ELECTRICAL ENGINEERS (Wireless Section), at 6.— 
C. F, Elwell: Design of Radio Towers and Masts: Wind Pressure 
Assumptions. 
INSTITUTION OF AUTOMOBILE ENGINEERS, at 7.30.—Col. P. H. Johnson : 
Improvements in Efficiency of Roadless Vehicles. 
THURSDAY, JANUARY 11. 
RoyAL AERONAUTICAL SOCIETY (at Royal Society of Arts), at 3.— 
R. A. Frazer: Testing Model Seaplanes (Juvenile Lecture). 
OpTIcaL Soctmty (at Imperial College of Science and Technology), at 
7.30.—C. Davidson: The Amount of Displacement in Gelatine Films 
shown by Precise Measurements of Stellar Photographs. —J. B. 
Barnard: The Use of Ultra- violet Light in Microscopy.—F. W. 
Preston: Pitch.—T. Y. Baker: A Prismatic Astrolabe. 
INSTITUTE OF METALS (London Section), (at Institute of Engineers, 
Inc.), at 8.—W. E. Hughes : Some Aspects of Electro-deposition. 
CAMERA CLUB, at 8.15.—J. S. Wells : Criticism of Members’ Prints. 
FRIDAY, January 12. 
ROYAL ASTRONOMICAL SocIETY, at 5.—Prof. A. 8S. Eddington and 
A. V. Douglas: The Progression of Stellar Velocity with Absolute 
Magnitude.—J. Evershed : Note on the Corona of 1908. 
MALACOLOGICAL Society (at Linnean Society), at 6. 
INSTITUTION OF HEATING AND VENTILATING ENGINEERS, INC. (at 
Engineers’ Club, Coventry Street), at 7.—Dr. B. R. Wingfield: 
Automatic Temperature Control. 
JUNIOR INSTITUTION OF ENGINEERS, at 7.30.—S. A. Stigant : Transient 
Phenomena arising in Transformers from Switching Operations. ; 
ROYAL SocrnTY OF MEDICINE (Ophthalmology Beptlon) at 8.30.— 
H. Butler: Some Unusual Cataract Operations.—C. Killick: The 
Treatment of Conical Cornea, ! 
SATURDAY, JANvArY 13. 
GILBERT WHITE FELLOWSHIP, at 2.15.—Visit to the Geological Museum, 
Jermyn Street. 
i: 
