432 



NA TURE 



[August 31, 1893 



ture of caoutchouQ, by Hermann F. Lueders. Caoutchouc has 

 no definite structure fer se, and all apparent structure is only 

 the result of the conditions under wKJch its coagulation from the 

 latex and subsequent solidification take place. 



SOCIETIES AND ACADEMIES. 



Paris. 



Academy of Sciences, August 21. — M. Lcewy in the chair. — 

 On the equations of motion of a solid body moving in an in- 

 definite liquid, by M. C. Maltezos. — On the alternations of 

 colours presented by gratings, by M. Georges Meslin. If the 

 achromatic fringes previously obtained by the author by means 

 of a grating are observed more and more closely to the latter, 

 they become more and more delicate, and certain colours begin 

 to appear. The black fringes remain dark, but of two con- 

 secutive bright fringes the one appears violet and the other 

 yellow ; the same phenomena occurs along the whole field, 

 which is covered with these two alternate colours. On moving 

 the microscope slowly forward, a great variety of colours is ob- 

 served, but the most usual are a 'mauye-violet associated with 

 yellow, green combined with pink, or blue accompanied by 

 white. The two colours in juxtaposition are thus nearly com- 

 plementary, and during this displacement the same appearances 

 recur several times, becoming more complex as the distance 

 diminishes. The black fringes become very fine, the interval 

 between two of them closes up, whilst the adjoining interval 

 M opens out and splits into coloured bands with a blue, pink, or 

 yellow axis. In every case the phenomenon retains its periodic 

 character. M. Meslin has succeeded in obtaining some very 

 instructive photographs of these fringes. — On two new diseases 

 of the mulberry, by MM. G. Boyer and F. Lambert. One of 

 these diseases is caused by a bacterium, the other by a fungus. 

 , The disease caused by the Bacterium mori, chiefly affects 

 young nursery mulberries, and arrests the development of their 

 branches. It is manifested by dark brown patches at some 

 points on the under side of the leaves and on the branches. 

 Artificial patches in the parenchyma and in the veins of the 

 leaves have been produced by inoculation. The bacterium 

 when isolated and cultivated on artificial solid media, gives 

 hemispherical colonies passing from white to yellow. The 

 fungus disease is the more common of the two. The buds and 

 1 eaves wither and dry up. The disease proceeds from the twigs 

 ^j to the branches and the trunk, and finally attacks the roots. 

 The grey colour assumed by the wood is caused by the myce- 

 lium of a parasitic fungus not yet completely isolated. 

 The mycelium is varicose, septiferous, and ramified. Its 

 colour passes from white to a pale yellow, and finally to 

 brown. — On the Rcogeny and stratigraphy of the coal 

 basins of Central France, by M. A. Julier. — The Cambrian 

 of the Herault, by MM. de Rouville, Delage, and Miguel. 

 The authors have recognised three groups in the Herault Cam- 

 brian which they provisionally name Anteparadoxidian, Para- 

 doxidian, and Postparadoxidian, corresponding to the Long- 

 mynd, Menevian, and Tremadoc groups respectively. In the 

 third group, corresponding to the Tremadoc slates and Lingula 

 flags, traces of Lingulac have been found. An important fact 

 conceining the stratigraphy of the country has been discovered 

 4n certain inversions extending over great lengths, unaccom^ 

 panied by any indication of violent dislocation or rupture. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Books. — The State of Para : Notes for the Exposition of Clilcago (New 

 York). — A Short Course in the Theory of Determinants : L. G. Weld (Mac- 

 millan). — A Treatise on the Theory of Functions: J. Harkness and F. 

 Motley (Macmillan). — A Select Bibliography of Chemistry, 1492-1892; H. 

 C. Bolton (Washington).— Cyclone Memoirs, No. V. : J. Eliot (Calcutta). — 

 Rainfall in South Australia r.nd the Northern Territoty, 1892 : C. Todd 

 (Adelaide). — Obseivaticns of the Tiansit of Venus, December g, 1874: H. 

 C. Russell (Sydney).— AUmbic Club, Reprints No. 3— Experiments on 

 Air: Hon. H. Cavendish (tidinburgh, Clay). 



Pamphlets. — Reprint on ihe (Jperations of the Department of Land 

 Records and Agriculture, Madras Presidency, 1891-92 (Madras). — The 

 State of Sao Paulo: A. A. Pinto (Chicpgo).^MeteoroIogy at the Paris 

 Exposition : A. L. Roth. — The Value of Hypnotism : T. Crisfield (London). 

 — The Geometrical Properties of the Sphere ; W. Briggs and F. W. 

 Edmonds^n (Clive). 



Serials.— L'Anthropologie, tome iv. No. 3 (Paris, Masson). — Journal 

 of the Franklin Institute, August (Philadelphia).— Astronomy and Astro- 

 Physics, August (Northfield, Minn.). — Quarterly Journal of the Royal 

 Meteorological Society, July (Stanford). — Meteorological Record, Vol. xii. 

 Kc. 48 (Stanford). — Katalog derEibliothek der Kaiserlichen Leopoldinisch- 



I to 3 

 1 Loopol- 



NO. 1244, VOL. 48] 



CaroHni.t:cher. Deuischen Akademie der NaiurforscVer, Liefg, 

 (Willioms and Ncrgaie).— Katalog der Hibliothek der Kaiserlichen Loopol- 

 dinisch-Carolinischen Deutschen Akademic der Nalurforscher, Vrierte, 

 Liefg. Band II. 8 {Willlanis and Norgate). — Sitzungsberichte der k. 

 Akademie der Wissenschaften. Math.-Naturw. Classe En'halt die Abliaod* 

 lungen aus dem Gcbiete der Chemie. Abthp. II b. 1892, Jrne, July, 

 October to December (Williams and Norgate). — Sitzungsberichte der k. 

 Akademie der Wissen.schaften. Math.-Naturw. Anatomiii and Physio- 

 logie, &C-, 1892, June, July, October to Pectmber (Williams and NorgaieX 

 Sitzurgsbericble der k. Akademie der Wissenschafieo. Math.-Naiurw. 

 Mineralogie, Krysrallographie, &c., 1892 July, October, November, and De- 

 cember (Williams and Norgate). — Sitzi'ngsberichte der k. Akademie der 

 Wissenschaften. Math.-Naturw. Mathematik, Astronomic. &c., iSga, 

 June, July, Octolwr, November, and December (Williams and Norgate).— 

 Register zu den bandtn q? bis 100 der Sitzungsberichte der Matheniati>ch. 

 Naturwissenchaftlichen classe der k. Akademie der Wissenschhafien xiii. 

 (Williamsand Norgate). — The Journal of the College of Science, Imperial 

 University, Japan, Vd. v. Part 4 (Tokyo).— Journal of theRo\al Micro- 

 scopical Socitty, August (Williams and Norgate) — Journal of the Marine 

 Pinlogical Association, new series, vol. 3, No. i (Dulau). — Journal of the 

 Polynesian Society, Vol. 2, No. 2 (Wellington). — Transactions and Proceed- 

 ings of the N.Z. In-titute, 1892, Vo. xxv. (Wellington). — Ergebnisse der 

 Meteorologischen Becbachtungen, Jahrg. 3 (Bremen).- — Journal de Physique 

 Aug. (Paris). — Zeitschrtft fur Physikalische Chemie, xii. Band, 2 Heft 

 (Leipzig). — Botanical Gazette, August (Bloomington, Ind.). — Bulletin of the 

 U.S. Geological Survey, Nos. 82 to 86, 50 to 96 (Washington). — Jahrfcuch 

 der k. k. geologischen Reichsanstalt, Jahrg. 1893, xHii. Band, 1 Hefi 

 (Williams and Norgate).— Morphologisches Jahrbuch, 20 Band, 2 Heft 

 (Williams and Norgate).— Mittheilungen von Forschungsrfisenden und 

 Galehrten aus den Deuischen Schutzgebieten, vi. Band, 3 Heft (Berlin, 

 MJttler). — The Asclepiad, No. 38, vol. x. (Longmans). — Journal <A the 

 Rojal Horticultural Society, vol. xvi. Part i (London). — Meieorologlsche 

 Zeitschrift, T?g3 January to August (Wien) — Himmel und Erde, Septemb« 

 (Berlin). — Bulletins de la Soci^te d'Anthropologie de Paris, tome quatrieme, 

 ivc s^rie, No. 7 (Paris). 



CONTENTS. PAGE 



Birds in a Village. By T. D. P 409 



A Mathematical Miscellany 410 



Our Book Shelf:— 



Vasey : " Grasses of the Pacific Slope, including 



Alaska and the Adjacent Islands" 411 



Ellis: "Reveries of World History, from Earth's 

 Nebulous Origin to its Final Ruin ; or, the 



Romance of a Star" 411 



Letters to the Editor: — 



The Publication of Physical Papers. — Alex. P. 



Trotter 412 



The Definition of " Heredity." — ^J. Spencer Smith- 

 son 413 



Sexual Colouration of Birds. — F. C. Headley ... 413 



Bird'.-i Steering Methods. — F.A.Lucas 414 



The Early Spring of 1893.— W. B. Crump ... 414 

 Mr. Love's Treatise on Elasticity. — A. B. Basset, 



F.R.S 415 



An Appeal to Mathematicians. — Kanhaiyalal ... 415 

 Arrangements for Work of Chemical Section of the 

 British Association. — Prof. JL^Emerson Rey- 

 nolds, F.R.S fgS3f , 416 



The Bacchus Marsh Boulder Becf<—K. D. Oldham . 416 

 Old and New Astronomy. — A. C. Ranyard; The 



Reviewer 416 



An Old Device Resuscitated.— F. W. Levander . . 416 

 Laws of Error in Drawing. — Arthur L. Haddon . 416 

 The Influence of Egypt upon Temple Orientation 



in Greece. By J. Norman Lockyer, l^l.S. . . . 417 

 British Association Meeting. By l^)f. Frank 



Clowes . 419 



George Brook 4W) 



Nctes . 4*' 



Our Astronomical Column : — 



Honorary Distinctions 4^5 



A Meteor 4*5 



A Bequest to Astronomy 4^5 



Oeographical Notes 4^3 



The Beaver Creek Meteorite. By Prof. B. J. 



Harrington 4^ 



Spangclite, a Remaikable Cornish Mineral. By 



H. A. Miers 42^ 



Desulphurisation of Iron. By John Parry .... 427 

 The Meteorological Obseivatory on Ben Nevis. 



{Illustrated.) 4»^ 



University and Educational Intelligence 43' 



Scientific Serials 43' 



Societies and Academies 43' 



Books Pamphlets, and Serials Received 43- 



