552 



NA TURE 



[April 9, 1896 



the tissues by means of the X-rays, by MM. A. Buguet and A. 

 Gascard. — Experiments relating to the action of the X-rays on 

 Phycoviyces nitens, by M. L. Errera. This Phycomyces was not 

 sensitive to these radiations. — On the Rontgen rays, by M. C. 

 Henry. General considerations as to the nature of the rays, 

 and a rhumS of their properties. — Reply to some observations 

 of M. Henri Becquerel relating to a note " On the principle of 

 an accumulator of light," by M. C. Henry. — Remarks on the 

 preceding, by M. Henri Becquerel. — -Safrol and isosafrol. 

 Synthesis of isosafrol, by M. C. Moureu. — On citronnellal and 

 its isomerism with rhodinal, by MM. P. Barbier and L. 

 Bouveault. — On the macroblasts of the oyster ; their origin and 

 localisation, by M. J. Chatin. — On the relations between Lepis- 

 viina 7>iyrmecophila and ants, by M. C. Janet. — On the tertiary 

 basin of the lower valley of the Tafna, by M. L. Gentil. 



Amsterdam. 



Royal Academy of Sciences, January 25. — Prof. Van de 

 Sande Bakhuyzen in the chair. — Prof. Lorentz showed a 

 number of photographs prepared by means of X-rays by Prof. 

 Rontgen, of Wiirzburg. — Prof. MacGillavry presented the dis- 

 sertation of Dr. D. MacGillavry on the aetiology and the 

 pathogenesis of congenital defects of the heart. — Mr. Jan de 

 Vries gave applications of the introduction of a third radius 

 vector into the bipolar system, so that the three poles lie in a 

 straight line. — Prof. Schoute treated Steiner's quartic surface 

 y^^ -f z^x^ -f x^y"^ = 2kxyz. — Prof. Engelmann communicated 

 the result of an investigation made by Dr. H. J. Hamburger 

 into the importance of respiration and peristaltics to the re- 

 sorption in the intestine. The resorption of liquids in the 

 alimentary canal increases with the intra-intestinal pressure, and 

 disappears altogether when this pressure is artificially lowered 

 to o or a negative value. — Prof. Kamerlingh Onnes made, on 

 behalf of Mr. D. van Gulik, a communication concerning an 

 investigation made, under the direction of Prof. Haga, at 

 Groningen, into the cause of the variation of resistance in 

 microphonic contacts brought about by electric vibrations. In 

 investigating the cause of the diminution of resistance through 

 electric vibrations generated in bad microphonic contacts, it 

 has been ascertained that the ends of a current-chain, when 

 brought very close together, attract each other if the wires are 

 exposed to Ilertz's waves. The arrangements being made with 

 proper care, the movable ends were seen under a microscope 

 to touch each other as soon as electric vibrations were generated 

 near them. The original air-gap must not be larjjer than four 

 microns, and a contact arisen in this way offered a resistance of 

 ^ ^ to the current. The removal of the element from the 

 chain had no influence upon the phenomenon. When the air- 

 gap was a few microns too large, then small sparks resulted on 

 the wires being acted upon by the above-mentioned waves. 

 Prof. Kamerlingh Onnes, starting from his theorem that Van 

 der Waals's corresponding states are dynamically similar, 

 inferred that the cooling of the gas in Thomson and Joule's 

 porous plug will, according to their experiments with hydrogen 

 (1862), become zero and turn into heating, with all gases, at 

 sufficiently high temperatures. The author extended the theorem 

 to thermo-dynamical similarity, and thus supplied the means 

 to find the dimensions of an apparatus to liquefy hydrogen, if 

 there is given one liquefying oxygen in a satisfactory manner. 

 Linde's and Dewar's methods were considered from this point 

 of view. The author also commented on his endeavours to get 

 a small self-cooling motor, liquefying oxygen, to be used as a 

 model for apparatus to liquefy hydrogen by doing work adiabat- 

 ically after the manner of Solvay, and intended to form part 

 of a series of theoretically perfect cooling apparatus. Finally 

 the author pointed out the superiority of Dewar's vacuum-jackets, 

 and their great importance for low temperature work. 



February 29. — Prof, van de Sande Bakhuyzen in the 

 chair. — Prof. Suringar described, in connection with previous 

 communications, some Melocacti, lately received from the 

 island of St. Martin, and belonging to the tribe of Melo- 

 cacti communes. They most nearly approach to the one 

 described by Link and Otto as M. communis, var. macro- 

 cephalus. They represent two types, which speaker has called 

 M. {communis) Linkii and M. {communis) croceus, the name 

 (omntmis between parentheses indicating the affinity. From a 

 comparison of the specimens discussed with those the author 

 formerly brought away from St. Eustace, and with the 

 description and drawing by Hooker of specimens from the 

 island of St. Kitts, it appears that in these islands, situated very 

 near each other, distinctly different, constant varieties of the 



NO. 1380, VOL. 53] 



common type have developed themselves. This had induced 

 the author to collect and to critically examine all the older 

 accounts, and especially the drawings by Lobelius (1576) down 

 to Miquel's monograph (1840). In anticipation of the Icono- 

 graphy, which he is preparing, he presented a treatise on 

 the subject, as a fourth contribution to the Transactions of the 

 Academy. It treats partly of crook-thorned Melocacti, to which 

 those of Lobelius and Besler belong, and of which the author has 

 found a variety of species in Aruba ; partly and especially of 

 Melocacti of the Melocacti communes tribe, peculiar to the 

 Northern Antilles, and which treatise will be illustrated by two 

 plates. — Mr. Jan de Vries made a communication concerning 

 Cartesian confocal ovals in connection with a hyperboloid of one 

 surface. — Prof. Rauwenhoff communicated the results of investi- 

 gations, made by Dr. H. F. Jonkman at Utrecht, into the 

 embryogeny of Angiopteris and Marattia. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Books.— The Island of Dr. Moreau : H. G. Wells (Heinemann).— A 

 Manual of Forestry: Prof. W. Schlich, Vol. i, 2nd edition (Bradbury).— 

 Die Vegetation der Erde. I. Grundziige der Pflanzenverbreitung auf der 

 Iberischen Halbinsel : M. Willkomm (Leipzig, Engelmann). — Monographic 

 der Gattung Euphrasia : Dr. R. v. Wettstein (Leipzig, Engelmann). — A 

 Handbook to the Birds of Great Britain : Dr. R. B. Sharpe, Vol. 3 (Allen). 

 — Rontgen Photographs : Profs. Reid and Kuenen (Dundee, Valentine). — 

 LeQons de G^ographie Physique : Prof. A. de Lapparent (Paris, Masson). 



Pamphlets. — Summary Report of the Geological Survey Department for 

 the Year 1895 (Ottawa). — A Laboratory Note-Book of Elementary Practical 

 Physics : _L. R. Wilberforce and T. C. Fitzpatrick. L Mechanics and 

 Hydrostatics (Cambridge University Press). — Kepler's Lehre von der 

 Gravitation ; Dr. E. Goldbeck (Halle a/s., Niemeyer). — Flora of West 

 Virginia : C. F. Mill.suaugh and L. W. Nuttall (Chicago).— The Classifica- 

 tion of the Chemical Elements : Prof. O. Masson (Melville). — The Jack 

 Rabbits of the U.S. : Dr. T. S. Palmer (Washington). 



Serials. — Fortnightly Review, April (Chapman). — Scribner's Magazine, 

 April (Low). — Geological Magazine, April (Dulau). — Imperial University 

 College of Agriculture, Bulletin Vol. ii. No. 5 (Tokyo). — Reliquary and 

 Illustrated Archaeologist, April (Bemrose). — Journal of the Royal Agri- 

 cultural Society of England, third series, Vol. vii. Part i (Murray). — Geo- 

 graphical Journal, April (Stanford). — Phonographic Quarterly Review, 

 April (Pitman).— Zeitschrift fiir Physikalische Chemie, xix. Band, 3 Heft 

 (Leipzig, Engelmann). — Annals of Scottish Natural History, April (Edin- 

 burgh, Douglas). 



CONTENTS. PAGE 



A Life of Louis Agassiz. By Prof. T. G. Bonney, 



F.R.S 529 



Fermentation Studies 530 



Palaeontology at the British Museum 531 



Our Book Shelf:— 



Saunders : " The Hymenoptera Aculeataof the British 



Islands" 532 



" Ostwald's Klassiker der exakten Wissenschaften " . 533 

 Streeter : " The Metric System of Weights and 



Measures" 533 



Letters to the Editor: — 



The Stress in Magnetised Iron.— Dr. Charles Chree 533 

 The Sacred Tree of Kum-Bum. {Ilhcstrated.) — A. 



Grigoriev 534 



A Jamaica Drift Fruit.— J. H. Hart 534 



The Rotation-Period of Venus.— Maxwell Hall . . 535 

 A Remarkable Meteor.— W. F. Denning . . 535 



Simple Huyghens' Apparatus for the Optical Lantern. 



— F. W. McNair 535 



The Management and Protection of Forests. II. 



By Sir Dietrich Brandis, K.C.I. E., F.R.S. ... 535 

 The Development of Butterflies under Artificial 



Conditions. By E. B. P 540 



A New Synopsis Animalium — Das Tierreich . . . 541 



Notes 542 



Our Astronomical Column: — 



The Royal Observatory at Edinburgh 545 



Comet Perrine-Lamp 545 



Boggiani's Recent Explorations amongst Native 

 Tribes of the Upper Paraguay River. {Illustrated.) 



By Prof. Henry H. Giglioli 545 



A New Human Skull of a Low Type from Brazil. 



By Prof. A. C. Haddon 548 



The Surface Dimensions of an Earthquake-Pulsa- 

 tion. By Dr. Charles Davison 548 



Science in the Magazines 548 



University and Educational Intelligence 549 



Scientific Serials 549 



Societies and Academies 550 



Books, Pamphlets, and Serials Received 552 



