;20 



NATURE 



[June 20, 19 18 



air-waves of the East London explosion of Jartuary 19, 

 1917. This is the complete report of the facts col- 

 lected on the occasion of the East London explosion 

 on January 19, 1917 (see Nature, February i, 1917, 

 p. 438, and August 2, 1917, p. 450, in which the main 

 conclusions were anticipated). — Sir Thos. Muir : The 

 quadratic relations between the determinants of a 

 4-by-8 array. The main idea of the paper was to 

 develop a convenient notation to facilitate the ! 

 xinalytical use of these arrays. | 



Capetown. \ 



Royal Society of South Africa, April 17. — Dr. J. D. F. i 



Gilchrist, president, in the chair.^ — Dr. J. D. F. i 

 Gilchrist : Luminosity in a South African earthworm 

 and its origin. Luminous earthworms are found on i 

 the slopes of Table Mountain. The luminosity pro- ; 

 ceeds from a discharge from the mouth and anus, , 

 which consists of cells heavily laden with inclusions i 

 of different kinds. The smaller inclusions consist ; 

 of a substance allied to fat, by the oxidation of which ' 

 the light is produced. The cells arise from the body \ 

 cavity, and are discharged into the anterior and pos- i 

 terior parts of the alimentary canal by definite com- 

 munications between the coelom and alimentary tract, i 

 — Sir Thomas Muir : Note on the adjugate of Bezout's ' 

 eliminant of two binary quantics.^I. B. P. Evans ^ 

 and Averil M. Bottoniley : The genera Diplocystis and i 

 Broomeia. Some specimens of Diplocystis have 1 

 recently been obtained by the authors from Portuguese j 

 East Africa, and this is the first recorded occurrence j 

 of the interesting genus from Africa. The African \ 

 material is not identical with that from Cuba, and the ; 

 authors describe it as Diplocystis Junodii, nov. spec. — 

 Ethel M. Doidge : South African Perisporiacese, ii. 

 Revisional notes. This communication consists of a 

 revision, due to work on a number of fresh collections j 

 of South African Perisporiaceae, of a previous com- | 

 munication on the subject by the author. — F. G. I 

 Cawston : F"resh-water snails as a cause of parasitic | 

 diseases. The author describes a number of snails 

 collected by him from various districts in South Africa, ' 

 and found to be. infested with the cercarial stages of ' 

 the various trematode worms. — J. Moir : Colour and j 

 chemical constitution, part iv. The remaining ! 

 phthaleins. The absorption spectra of complex ■ 

 phthaleins are described, these being partly duplex I 

 compounds of the phenol-anthrol type and partly of i 

 a new class [e.g. thymol-naphthol) derived from j 

 thymoylbenzoic acid. The additive nature of the ! 

 effects of different substitutions is emphasised by 

 means of a table giving the numerical value of the 

 change of wave-length for diffe.ent substituting 

 groups. 1 



BOOKS RECEIVED. 



rh< ( hcniical Analysis of Iron. By A. A. Blair. 

 8lh edition. Pp. 318". (Philadelphia and London : 

 J. B. Lippincott Co.) 21s. net. 



Fisheries of the North Sea. By N. Green. Pp. vii 

 + 178. (London: Methuen and Co., Ltd.) 4^. 6d, 

 net. ^ 



Map Work. By V. S. Bryant and T. H. Hughes. 

 Pp. 174. (Oxford: Clarendon Press.) 5s. net. 



Is Man the Product of Evolution? By S. J. 

 Whitmee. Pp. 24. (London : Headlev Bros, Ltd.) 

 6d. net. 



Wayfarings : A Record of Adventure and Liberation 

 In the Light of the Spirit. Bv W. J. Jupp. Pp. 234. 

 (London: Headley Bros., Ltd.) 6i'. net. 



Methods of Measuring Temperature. By Dr. E. 

 Griffiths. Pp. xi+176. (London: C. Griffin and 

 Co., Ltd.) 85. 6d. net. 



NO, 2538, VOL. lOll 



DIARY OF SOCIETIES. 



THURSDAY, June 20. 



RnvAi. SoriKTV, at 4.30.— Crooin:m Lecture: The Physiological Basis of 

 Thirst : Major W. B. Cannon. 



LiNNF.AN Society, at 5. — Les esploes d'Alpheidae rapportiies par M. J. 

 Stanley Gardiner de I'Oc^an Indien : Prof. H. Coiitiere— -(i) A Selection 

 of Fer<iinand Bauer's Landscapes, c. 1784. C2) Ten British Plants : G. 

 Claridge Druce. — Exhibition of Lantern-slides representing a Series of 

 Intermediate Forms of the Diatom Genera Navicula and t ymbella : Sir 

 Nicolas Yermoloff. — Sex-segregation in the Bryophyta : R. J. Collins.— 

 Phenological Observations in an Elementary School : A. O. Walker. 



RoYAi, Society of Arts, at 4.30.— Indian Cotton and the Cotton iiiiH- 

 Itidiistry : The Hon. Sir Dinshaw E. Wacha. 



MONDAY, June 24. 



Aristotelian Society, at 8. — The Moral Argument for Theism : Rev. 

 W. R. Matthews, 



Royal Geographical Society, at 8.30.— Address by the Hon. Arthur 

 Meighen, Canadian Minister of the Interior, attending the Iniperi.-il 

 Conference. 



TUESDAY, June 25. 



Royal Anthropological Institute, at 5. — Sociology of the Ea.st Coast 

 People, Formosa : S. Ishii. 



Akronauticat, Society (Central Hall, Westmi' ster), at 8. — Wilbur Wright 

 Memorial Lecture : Some Out-Standing Problems in Aeronautics : Prof. 

 W. F: Durand. 



THURSDAY, June 27. 



Royal Society, at 4.30. — frohable Papers: Periodic Trrotational Waves 

 of Finite Height : Prof. T. H. Havelock.— The Diflfraction of Electric 

 Waves by the Earth : Dr. G. N. Watson.— Concerning Emotive Phe- 

 nomera. II.: Periodic Vari-itions of Conductance of the Palm of the 

 Human Hand: Dr. A. D. Waller.— The Mechanism and Control of 

 Fibrillation in the Mamma'ian Heart : Prof J. A. MacWiUiam. — The 

 Development of the Sea Anemones, Actinoloba tiianthus and Adaiusia 

 palliaia : Dr. J. F. Gemmill. — The Occurrence of Multinucleate Cells in 

 Vegetative 'I'issues : R. Reer and Agnes Arber. — The Epithelial Sheath of 

 Hertwig in the Teeth of Man, with Notes on the Follicle and Nasmyth's 

 Membrane: Dr. J. H. "Slwrnm^ty.— And other Papers.' 



FRIDAY, June 28. 

 Physical Society, at 5. — A New Method of Measuring Alterna'.ing 

 Currents and Electiic Osrillatiors : I. V\ illiams. — Demonstratiun of 

 Coupled Vibrations : Prof. E. H. Barton and Miss H. M. Browning. 



CONTENTS. PAGE 



Masonry Dams and Irrigation Work. By Dr. 



Brysson Cunningham 301 



Medical Electriiity. By A. C. J. 302 



Industrial Welfare and Health 302 



Our Bookshelf 303 



Letters to the Editor: — 



The Food of the RooV.— Dr. Syd: ey H. Long; 



The Writer of the No^e 304 



A Proof that any Aggregate can be Well-ordered. — 



Philip E. B. Jourdain ... 304 



Con.struction for an Approximate <)uadrature of the 



Circle.— Glenny Smeal ; David Baxandall . . 304 



Inter-A)lied Scientific Food Commission 304 



The New Star in Aquila 306 



The New Sy?tem of Time-keeping at Sea. By 



Dr. A. C, D. Commeln 307 



Damascene Steel. By H. C. H. C 308 



Notes 309 



Our Astronomical Column : — 



Nebulosity in Star Clusters 314 



Interpretation of Stellar Types 314 



The Straihmore Meteorite 314 



The South-Eastern Union of Scientific Societies . 314 

 The Tieatmeiit of Malaria. By Capt. F. W. 



O'Conror 315 



Scientific Problems of Disabled Soldiers 316 



Climatology of Paris 316 



The Story of a Grass. By Dr. A. B. Rendle, F.R.S. 317 



University and Educational Intelligence 318 



Societies and Academies 318 



Books Received 320 



Diary of Societies 320 



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Editorial Communications io the Editor. 

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