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A 579. A Determination of the Deflection of Light by the Sun’s Gravitational Field, from Observations 
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Prof. A. S. Eddington, F.R.S., and Mr. C. Davidson. Pp. 43; 1 Plate. Price 4s. 6 d. 
A 580. A Critical Study of Spectral Series. Part V.—The Spectra of the Monatomic Erases. By 
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A 581. Title, Contents, Index, &c., Vol. 220. Pp. 10. Price 6 d. 
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A 582. Some Measurements of Atmospheric Turbulence. By Lewis F. Richardson. Pp 28; 1 Plate. 
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A 583. On a Theory of the Second Order Longitudinal Spherical Aberration for a Symmetrical Optical - 
System. By T. Y. Baker, B.A., Instructor Commander, R.N., and L. N. G. Filon, M.A., 
D.Sc., F R.S., Goldsmid Professor of Applied Mathematics and Mechanics in the University 
of London. Pp. 43. Price 3s. 6d. 
A 684. Investigations on Lightning Discharges and on the Electric Field of Thunderstorms. By 
C. T. R. Wilson, F.R.S., Reader in Electrical Meteorology in the University of Cambridge 
and Observer in Meteorological Physics at the Solar Physics Observatory, Cambridge. 
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A 585. Researches on the Elastic Properties and the Plastic Extension of Metals. By W. E. Dalby, 
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A 586. The Stress-Strain Properties of Nitro-Cellulose and the Law of its Optical Behaviour. By 
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Price 4s. 
Series B. — Biological. 
B 369. The Morphology and Evolution of the Ambulacrum in the Echinoidea Holedypoida . By 
Herbert L. Hawkins, M.Sc., F.G.S., Lecturer in Geology, University College, Reading. 
Pp. 104 ; 9 Plates. Price 8s. 6 d. 
B 370. On the Structure of Lysorophus, as Exposed by Serial Sections. By W. J. Sollas, Sc.D., 
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B 371. Title, Contents, Index, &c., Vol. 209. Pp. 10. Price 6 d . 
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B 372. The Respiratory Exchange of Man During and After Muscular Exercise. By J. M. H. Campbell, 
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B 373. The Microscopical Features of Mechanical Strains in Timber and the Bearing of these on the 
Structure of the Cell-wall in Plants. By Wilfrid Robinson, D.Sc., Lecturer in Botany, 
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B 374. On a Form of Botrytis cinerea , with Colourless Sclerotia. By William B. Brierley (Roth- 
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B 375. The Irish Eskers. By J. W. Gregory, D.Sc., F.R.S. Pp. 37. Price 4s. 
B 376. The Thermo-Elastic Properties of Muscle. By A. V. Hill, F.R.S., and W. Hartree. Pp. 21. 
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