404 
been shown that the absorption’ of a given wave-length 
in a solid varies as the fourth power of the atomic 
number of the solid, whilst for a gas the primary 8 
jonisation also varies as the fourth power of the 
atomic number of the atom ionised, leads to the con- 
clusion that absorption in solids (apart from scatter- 
ing) is due throughout to the produetion of f particles. 
Expressions are found for the fall in the constant of 
proportion between the absorption per atom and N* 
when a K line ceases to be excited, and when an 
L. line ceases to he excited.—M. Rindl: Note on the 
occurrence of daphnin in the arthrosolen. 
has determined the presence of daphnetin and glucose 
in Lasiosiphon polycephalus, a perennial shrub which» 
flowers in August and September, known to the South 
African farmers as Januariebosje, and assumes that: 
the glucoside daphnin has been present and ‘hydrolysed: 
in the process of extraction. 
BOOKS RECEIVED. 
Manual of Psychiatry. By Dr. J. Rogues de Fursac 
and Dr. A. J. Rosanoff. Fourth edition. Pp. xi+522. 
(New York: J. Wiley and Sons, Inc. ; London ;:Chap- 
man and Hall, Ltd.) tos. 6d. net. 
Food and Health. By Prof. H. Kinne and A. M 
Cooley. Pp. vit+312. (New York: The Macmillan 
Co.; London: Macmillan and Co., Ltd.) 3s, net. 
Theoretical Chemistry from the Standpoint of Avo- 
gadro’s Rule and Thermodynamics. By Prof. W. 
Nernst. Revised by H. T. Tizard. © Pp. -xix+853. 
(London: Macmillan and Co., Ltd.) rss. net. 
Bacon’s Large-Scale Map of the Salonika Battle 
Front. (London: G. W. Bacon and Co., Ltd.) 1s. 
net. 
Tropical Agriculture. By Dr. E. V. 
Xvili+373. (New York and London: 
and Co.) tos..6d. net. 
Scheme for Maternity and Child Welfare Work. By 
Wilcox. Pp. 
D. Appleton 
Misses I. Macdonald and K. C. Atherton. (London : 
Royal Sanitary Institute.) 1s. net. 
Functions of a Complex Variable. By T. M. Mac- 
Robert. Pp. xiv+ 295. Macmillan and 
Co., Ltd.) 12s. net: 
A Laboratory Course of Practical Electricity for 
Vocational Schools and Shop Classes. By M. J. Arch- 
bold.” Pp. ix+211+/Exp. 98. (New York: The Mac- 
millan’ Co. ; ‘London : a and. €o., Ltd.) 
5s. net. 
A ‘Critique of ‘the Theory of volition By Prof. 
T. H. Morgan. Pp. x+197. | (Princeton : University 
Press; London : Oxford University Press.) 6s, . net. 
Human Physiology. | By P.:G.) Stiles. . Pp. 405. 
(Philadélphia and London: W.».B, Saunders Co.) 
Os. 6d. net. ae 
Farm Spies : How the Boys Irivestigated Field Crop 
Insects? By ‘Prof.’ A. F. Conradi and W. ‘Av Thomas. 
Pp. xi+16e.. -(New: York: The Macmillan Co. ; ; 
London : Maemillan'and Co., Ltd.) 2s; nét? 
(London : 
DIARY OF SOCIETIES. 
THURSDAY, Janvary 18. 
Linnean Society, at 5.—The Comparative Morphology of the Sorus of 
Ferns: Prof, F. O. Bower. 
MATHEMATICAL SocteTy - at 
5.30.—Some Aevmptotic Formule i in Com- 
binatory Analysis: G. H. Hardy and S. beset arag Hat Solutions! 
of Ordinary Differential Equations of the First Order: M; J. M, Hill: = 
The Nature of a ‘Moving Electric Charge and:its Lines of Electric Force? 
H. Bateman. 
Rovat Society 4F Arvs, at 4.30 —Between the Tigris ‘and thé Indus. The 
a n-i-Israél : Sir T.. H. Holdich. 
HEMICAL Socirry, at. 8.—Alloys of Copper and Tin, Aluminium and 
. Gold : Col. Cc. T. Heycock. | 
FRIDAY, January i9. 
Royar InsTITUTION, at 5.30.~Soap Bubbles of Long Dursbione Sir 
James Dewar. 
NO. 2464, VOL. 98] 
NATURE 
The author: 
[JANUARY 18, 1917 
INSTITUTION OF MECHANICAL ENGINEERS, at 6.—The Manufacture of 
Ca es at the L.C.C, Paddington ‘Technical Institute: A. G, Cooke, ec) 
. Gow, and W. G, ‘Tunnicliffe. : 
SATURDAY, January 20. 
Rovav Institution, at 3.—The. Lakes and Mountains of Central Africa : | : 
A. R, Hinks. 
MONDAY, JaNnvuary 22 ; 
Royat GEoGRAPHICAL SOCIETY, at 8.30. —Yunnan and the West River of | 
Cmna: E, C. Wilton. 
ARISTOTELIAN SOcIETY, at fa Mae in the Light of Recent Develop- ‘ 
ments in Philosophy: C, E. M. Joa’ 
TUESDAY, Pea 23. Seabii 
Royat INstiruTion, at 3.-—The Old Brain and the New Brain, said toeir 
Meaning: Prof. C. S. Sherrington. 
' Iystirurion or Civi ENGINEERS, at 5-30.—The Physical Features of 
‘““Acam’s Bridge,” and the Currents across it, considered as affecting the | 
Proposed Construction of a Railway cpanceeiny India. with Ceylon: 
F. J. Waring. Fe 
WEDNESDAY, Jat Work “th 24. 
oe Society or ARTS, at 4.30.—Relief Work in Betetth: W. A. M. ) 
oode, 
GEOLOGICAL SOCIETY, at 5.30.—Easter Island: W. Scoresby Rouiledkee , 
THURSDAY, JANvuary 25. 
Roya Society, at 4. 30.—Probable Papers: The Dynamics of Revolving” 
Fluid: ‘Lord Rayleigh. —Spectroscopic Observations on the Active 
Modification of Nitrogen. V. : Hon. R. J. Strutt.—Magnetic Induction 
and its: Reversal in Spherical Iron Shells: Profs. J. W. Nicholson and | 
E. Wilson.—The ‘Iwo dimensional Mution of a Plane Lamina in an 
Resisting Medium = S. Brodetsky. 
FRIDAY, JANUARY 26, 
Royac InsTITUTION, at 5-30. —Fpicurean Philosophy : Prof. G. Murray, ’ 
Puysica Society, at 5.—A Clock of Precision: C. O. Rartrum.—The 
Effect of the Water Vapour in the Atmosphere on the Propagation of 
' Electromagnetic Waves: Dr. F. Schwers. 
SATURDAY, Janvary 27. u 
Rovat INSTITUTION, at 3.—The Lakes and Mountains of Central Africa 
A. R. Hinks, 
CONTENTS. PAGE 
An Appreciation of Work. By Prof. W. See le - 385. 
Adjustment.of Observations . - ce Bees 
Noxious Insects. By F. V. T. . . BaP e 386, 
History of Mathematics. ~ Gh B. M. waiter ¢ AOR 
Our Bookshelf... | ce ty Ser 
Letters to the Editor:— 
The Permanence of Finger-print Patterns. —Henry 
Faulds; Sir W. J. Herschel, Bart. - OT 388: 
The Date ‘of the ‘Introduction of the Term “ Meta- 
bolic.” —Prof. D: Fraser Harris ) cee 389 
Cultural Amcébze from the: Intestine of Mai.—Dr, 
H. B. Fanthami ; The Reviewer. . bods caggoly398t 
Flour Standards. By ‘William Jago. 0+ "a: 
Mortality Tables and Expectation of Life 
ope oa 
hee 
ro) 
™ 
Prof, Thomas Purdie, F.R.S.. By J.-C. I. 
Dr. N. H. J. Miller. By Dr. E. A Russell. v2! 392 
Notes : © 32.2 eee 
Our Astronomical Column :— , > eeite 
Aurora Borealis- os... <a g¢ eens: see 
Clouds on Mars Sie) at eg ca a) alee 
The Cepheid Variables. . : 397 
Geological Workin Canada and Australasia. “(its 
ivated:)’ By'G, (ALJ. C00. 2.0% Ree ee 
Science in Public Schools . Abo: TEialas? 2yrao ela 
Fertilisers and Agricultural Production 3 Se), fae SOS 
Italian Meteorology. LyR.C.M. ........ 401 
‘Ethnobotany of at pet Indians) ait. 2 eee 
University and Educational Intelligence +. go2 
Societies and Academies. ... . ... . es 0,+ 0 1 GOB 
Booke Received: ~.+; 5.5 5 + - «te ee sn cre * ee Om 
Diary of Societies ..... mies f ~ 404 
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