5°4 



NA TURE 



[March 22, 1906 



made with the large equatorial of the Observatory of 

 Bordeaux : E. Esclangon. The observations were made 

 on March 6 and 7. The comet had the appearance of a 

 star of 105 magnitude, surrounded by a very feeble 

 luminosity. — The electromotive forces of contact between 

 metals and liquids, and an improvement in the iono- 

 graph : Charles Nordmann, Diagrams are given of the 

 apparatus and of a record of the recording instrument for 

 a period of twelve hours. — The sympathetic vibration of a 

 string giving a low note under the influence of one giving 

 a higher note, and the possible consequences arising 

 from this : Edmond Bailly. It has been held up to now 

 that a note cannot produce a sympathetic vibration in a 

 string of lower pitch than itself. The author describes 

 an experiment leading to a contrary conclusion. — The 

 action of hot sulphuric acid on salts of platinum and 

 iridium in the presence of sulphate of ammonium : Marcel 

 Delepine. Both these metals are dissolved by boiling 

 sulphuric acid in very appreciable quantities. Complex 

 acids appear to be formed in which the sulphuric acid is 

 not precipitable by barium chloride. — The action of peroxide 

 of nitrogen on ammonia and some ammoniacal salts : MM. 

 Besson and Rosset. When liquid ammonia at —90° C. 

 is added to solid nitrogen peroxide at the same tempera- 

 ture there is a violent explosion. The reaction can be 

 moderated by working with ammonia gas at —20° C. ; the 

 products are nitrogen, nitric oxide, and ammonium nitrate. 

 — The action of silicon chloride upon cobalt : Em. 

 Vigouroux. At a high temperature silicon chloride is re- 

 duced by cobalt, a volatile metallic chloride being formed 

 and a robaltosilicon remaining behind. The amount of 

 silicon in this latter compound tends to the silicide Co,Si 

 as a limit. — The dilactide of lsevorotatory lactic acid : E. 

 Jungfleisch and M. Codchot. — A method of determin- 

 ation of the foreign materials contained in cocoa and 

 chocolate : F. Bordas and M. Touplain. The substance 

 is treated with carbon tetrachloride mixed with varying 

 proportions of benzene, so as to get a range of density 

 between i-6 and 1-346. A separation of the materials of 

 different densities is readily effected. — Polyvalent anti- 

 oxydase serum : C. Gessar. — Contribution to the systematic 

 anatomy of some kinds of ferns : Ferdinand Pelourde. — 

 Nuclear fertilisation in the Mucorinea; : M. Dangeard. — 

 Hylochoerus Meinertzhageni : Maurice de Rothschild and 

 Henri Neuville. — The structure of the caecum or filiform 

 appendices of the middle intestine of Phyllium crurifolium : 

 L. Bordas. — The comparative anatomy of the Sipuncu- 

 lidae : Marcel A. Herubel. — The evolution of the supposed 

 coccidia of cephalopods : Th. Moroff. — A new disease of 

 the trout : L. Leger. — The analysis of tubercle bacilli : 

 G. Baudran. Separate analyses were made of dead and 

 living bacilli. The former gave lecithin, cholesterin, and 

 fat, cellulose, nuclein, and albumenoid materials. The 

 living bacilli gave, in addition, an anaeroxydase and an 

 alkaloid. — The reaction of the blood a function of nutri- 

 tion : Jean Gautrelet. There is an absolute parallelism 

 between the apparent alkalinity of the blood and the activity 

 of the organic exchanges as measured by the amount of 

 haemoglobin. — The Pleistocene glaciers in the valleys of 

 Andorre : Marcel Chevalier. — 1 he volcanoes of the 

 Livradois and Comte, Puy-de-D6me : Ph. Glangeaud. — 

 The tectonic of the Ivre.e and Strona zones : Emile 

 Argrand. — The diatom-bearing sediments of the region of 

 Lake Tchad: Paul Petit and H. Courtet. 



DIARY OF SOCIETIES. 



THURSDAY, March 22. 



Royal Society, at i.^o.—Bdkerian Lecture : Recent Advances in 

 Seismology; Prof. J. Milne, F.R.S. — On Melbods whereby the Radiation 

 of Electric Waves may be mainly confined to Certain Directions, and 

 whereby the Receptivity of a Receiver may be restricted to Electric 

 Waves emanating from Certain Directions : Chevalier G. Marconi. — A 

 Note on the Theory of Directive Antenna; or Unsymmetrica] Hertzian 

 Oscillators: Prof J. A. Fleming, F.R.S. 



Institution of Electrical Engineers, at 8. — Electrical Equipment of 

 the Aberdare Collieries of the Powell Duffryn Co. : C. P. Sparks.— Elec- 

 tric Winding considered Practically and Commercially : W. C. Mountain. 



Royal Institution, at 5. — Internal Combustion Engines: Prof. B. 

 Hopkinson. 



FRIDAY, March 23. 



Royal Institution, at 9.— Imperial Defence : Lord Roberts. 



Physical Society (University College), at v-On Unilateral Electric 

 Conductivity over Damp Surfaces: Prof. F. T. Troulon, F.R.S.-The 



NO. 1899, VOL. 73] 



Construction and Use of Oscillation Valves for Rectifying High Fre- 

 quency Electric Currents : Prof. J. A. Fleming, F.R.S.— On the Use of 

 the Cymometer for the Determination of Resonance Curves : G. B. Dyke. 



Institution of Civil Engineers, at 8.— Waves : F. K.Stevens. 

 SA TURD A Y, March 24. 



Royal Institution, at 3.— The Corpuscular Theory of Matter: Prof. 

 J. I. Thomson, F.R.S. 



MONDAY, March 26. 



Society OF Arts, at 8.— Fire, Fire Risks, and Fire Extinction: Prof. 

 Vivian B. Lewes. 



Institute of Actuaries, at 5.— Some Aspects of Registration of Title 

 to Land : J. R. Hart. 



TUESDA Y. March 27. 



Royal Institution, at 5.— The Influence of Geology on Scenery: Dr. 

 J. E. Marr, F.R.S. 



Institution of Civil Engineers, at 8.— Continued Discussion: The 

 Outer Barrier, Hodbarrow Iron Mines: H. Shelford Bidwell.— The Har- 

 bours of South Africa : C. W. Methven. 



WEDNESDAY, March 28. 



Society of Arts, at 8. — Coal Conservation, Power Transmission and 

 Smoke Prevention : A. J Martin. 



THURSDAY, March 20. 



Royal Society, at 4.30.— />■',,' /, i',i/; >-s : On the Dilatational Stability 

 of the Earth : Lord Rayleigh, O.M., P.R.S. On the Observations of 

 Stars made in some British Stone Circles. Second Note : Sir J. 

 Norman Lockyer, K.C.E., F.R.S. 



Royal Institution, at 5. — Internal Combustion Engines: Prof. B. 

 Hopkinson. 



Institution of Electrical Engineers, at 8. — Adjourned r 



Electrical Equipment of the Aberdare Collieries of the Powell Duffryn 

 Company : »C. P. Sparks. — Electric Winding, considered Practically 

 and Commercially : W. C. Mountain. 



FRIDA Y, March 30. 



Royal Institution, at 9. — Recent Progress in Magneto-optics: Prof. P. 

 Zeeman. 



SA TURD A Y, March 31. 



Royal Institution, at 3. — The Corpuscular Theory of Matter: Prof. 

 J.J. Thomson, F.R.S. 



CONTENTS. page 



The Bantu Speech of Southernmost Africa. By 



Sir H. H. Johnston, K. CM. G. . 4S1 



Mining Law. By Bennelt H. Brough 4S2 



Organic Chemistry applied to Physiology. By 



Prof. Benjamin Moore 4S3 



Our Book Snelf :— 



Pierpont : " Lectures on the Theory of Functions of 



Real Variables," vol. i 4S3 



Edmunds: "Sound and Rhythm." — Prof. John G. 



McKendrick, F.R.S 483 



Robertson and Bartholomew : " Historical and 

 Modern Atlas of the British Empire, specially pre- 

 pared for Students " ; " Philips' Model Atlas" . . 4S4 

 Watson : " Natural Science in Hygiene, or the Life- 

 History of the Non-Bacterial Parasites affecting 



Man."— Prof. R. T. Hewlett 484 



Letters to the Editor: — 



A Plea for Absolute Motion. — Norman R. 



Campbell .... 484 



Interpretation of Meteorological Records. — Dr. John 



Aitken, F.R.S. . 485 



Agricultural Educalion and Colonial Development. — 



Dr. J. Walter Leather 4S5 



Peculiar Ice Formation. — Rev. A. Irving; W. 



Larden 485 



American Observations of the Total Solar Eclipses 

 of 1900 and 1901. (Illustrated.) By Dr. William 



J. S. Lockyer 486 



Agriculture and the Empire. --By Sir W. T. Thisel- 



ton-Dyer, K.C.M.G., F.R.S 488 



Notes 490 



Our Astronomical Column : — 



Discovery of a New Comet (1906c) 494 



Comet 1906* 494 



Comet 1906a (Brooks) 494 



A Programme of Solar Research 494 



Harvard College Observatory 494 



Catalogue of 3799 Bright Stars 495 



Eclipse Observations at Catania 495 



Micrometer Measures of Struve Double Stars .... 495 

 Some Applications of the Theory of Electric Dis- 

 charge through Gases to Spectroscopy. (With 

 Diagrams.) By Prof. J. J. Thomson, F.R.S. ... 495 

 Microscopic Aquatic Plants and their Place in 



Nature. By Dr. F. E. Fritsch 499 



University and Educational Intelligence 500 



Societies and Academies 501 



Diary of Societies 504 



