522 



NATURE 



[October 20, 19 10 



of definition was observed, and in actual use thie per- 

 formance was satisfactory. It is absolutely essential for 

 the success of the method that the mirror be quite 

 enclosed, and exposed only to an. atmosphere of amyl 

 acetate so as not to be allowed to dry, for about one 

 hour after the solution has been flooded on, as, without 

 this precaution, a perfectly uniform film cannot be 

 obtained. — Dr. Henry Wilde : The origin of cometary 

 bodies and Saturn's rings. The first part of this 

 paper is a further exposition of the author's theory 

 of the origin of comets and cometary bodies from the 

 interior of the planets of the solar system, with new 

 illustrations drawn from experimental mechanics. Dr. 

 Wilde considers that the recently discovered satellites of 

 Jupiter and Saturn, which have retrograde motions, are 

 planetary ejectamenta, and from their comparative minute- 

 ness are hardly entitled to rank as satellites. The theory 

 advanced by Olbers, the illustrious discoverer of Pallas and 

 Vesta, that the planetoids are fragments of an exploded 

 planet, finds confirmation in the great irregularities of 

 their orbits and the direct and retrograde motions of 

 cometary bodies. The author next discussed the origin of 

 Saturn's rings, which has for a long time engaged the 

 attention of natural philosophers. Kant assumed that 

 Saturn at an early period of its history had the character- 

 istics of a comet, and that its tails contracted upon the 

 planet and formed a ring. Laplace supposed the rings to 

 be the original nebular substance uncondensed into the 

 form of a satellite. The author ventures to affirm that 

 the rings are the ejectamenta of Saturn when its diminish- 

 ing energies were insufficient to eject a comet with its 

 train of meteorites, or a cometary satellite. Dr. Wilde 

 adduced evidence to show that the interior rings were 

 formed some time subsequently to the outermost one, 

 which is separated from the others by an annular space 

 of 2585 miles. The author has drawn up a t.able of 

 distances of the rings from Saturn and the times of their 

 revolutions, calculated from his measurements of the 

 photographs recently taken at the Lick Observatory. 

 New South Wales. 

 Linnean Society, August 31. — Mr. C. Hedley, president, 

 in the chair. — Dr. H. G. Chapman : A contribution to 

 the study of the precipitins. The paper records the results 

 of an examination, by gravimetric methods, of the rela- 

 tions of the interacting substances in precipitin inter- 

 actions. It was found that the amount of precipitate 

 yielded by each antiserum was a fixed quantity for each 

 cubic centimetre of antiserum, provided that sufficient 

 homologous protein was present to precipitate completely 

 the precipitin in the antiserum. In total interactions the 

 weight of precipitate was proportional to the amount of 

 antiserum. In partial interactions the weight of pre- 

 cipitate increased with ascending weights of homologous 

 protein. Since the precipitates are derived mainly from 

 the antiserum, it has been possible to determine the weight 

 of the anti-substance in the antiserum. Consequent on 

 the results of the gravimetric study of the interaction, a 

 method has been devised to separate the proteins of closely 

 allied species. Suggestions are made as to the composi- 

 tion of a precipitin-antiserum, as regards the com- 

 ponents, giving rise to general avian and specific inter- 

 actions. The preliminary results of the application of the 

 test to the differentiation of vegetable proteins ate re- 

 corded. They show that a group-specificity holds for 

 proteins of vegetable origin. The derivation of precipitate 

 from antiserum has not been sufficiently considered in 

 relation to deviation of complement. — Dr. A. J. Turner : 

 Revision of Australian Lepidoptera, part v. Part v. deals 

 with the subfamily Geometrina; of the family Geometrida?, 

 comprising 40 genera and 124 species. The number of 

 known species has been greatly added to, especially from 

 the northern part of .\ustralia, since the publication of 

 Mr. Meyrick's " Revision of Australian Lepidoptera, 

 No. ii., GeometridjE, " in the society's Proceedings for 

 1887 (p. 835). — A. F. Basset Hull : Description of a fossil 

 Chiton (Mollusca) from north-west Tasmania. The de- 

 scription is based on an example of a median valve, which 

 shows the species to have been allied to, but distinguish- 

 able from, Lorica affiius, .^shby and Torr, and the living 

 L. volvox. Reeve. The specimen was collected by Mr. 



NO. 2 1 3S. VOL. 84] 



W. S. Dun from the base of the Turritella sandstone at 

 the foot of a bluff between Wynyard and Table Cape. 

 The beds are referred to the Jan Jukian by Hall and 

 Pritchard ; that is to say, they are near the base of the 

 Tertiary, as developed in southern Australia. Victorian 

 geologists correlate them with the marine series at Spring 

 Creelc. The Eocene age attributed to these beds must be 

 regarded as purely relative. 



DIARY OF SOCIETIES. 



FRIDAY, OcTORER 21. 

 Institution of Mechanical Engineers, at 8. — The Standardisation 

 of Locomotives in India, igio : Cyril Hitchcock. 



WEDNESDAY, October 26. 

 British Astronomical Association, at 5. — Annual Meeting. 



FRIDAY, October c8. 

 Physical Society, at 5. — Demonstration of a New Method for producing 

 High-tension Discharges: Prof. Ernest -Wilson and W. H. Wilson.— 

 The Behaviour of Steel under combined Static Stress and Shock : 

 F. Rogers. 



contents. page 



Recent Progress in Psychical Research. By Sir 



Oliver Lodge, F.R.S 489 



Fossil Club-mosses and Ferns. By D. H. S. . . 490 



The Collected Works of Huygens. By J. L. E. D. 491 



A Primer on Coal Mining 492 



Our Book Shelf 493 



Letters to the Editor: — 



Early Burial Customs in Egypt,— Prof. W. M. 



Flinders Petrie, F.R.S 494 



Lord Morton's Quagga Hybrid and Origin of Dun 

 Horses. — Prof. James Wilson ; Prof. J. C. 



Ewart, F.R.S ..... 494 



Tests for Colour-blindness. — Dr. F. W. Edridge- 



Green ; The Reviewer 495 



Water Vapour on Mars. — Prof. Frank W. Very . . 495 



A Caution.— E. A. S 496 



Dr. John Peile : A Correction.- The Writer of the 



Article 496 



The Centenary of Berlin University 496 



Town-planning. By A. E. Crawley 498 



The Melanesians of British New Guinea. {Illus- 

 trated.') By S. H. Ray 499 



The Centenary of Filippo Cavolini 500 



John Willis Clark. By Dr. Sidney F. Harmer, 



F.R.S 501 



Prof. Maurice Levy 502 



Notes 502 



Our Astronomical Column : — 



A Bright Projection on Saturn 5°7 



Spectrum and Radial Velocity of (^ Persei 5*^7 



Metcalf's Comet, igioi') 507 



Comets and Electrons 5°7 



Measures of Double Stars 507 



Recent Results in Solar Physics 5°7 



The Ninth International Conference on Tuber- 

 culosis 507 



The International Scientific Congress at Buenos 



Aires. By Prof. C. D. Perrine 509 



Recent Investigations on the Cultivation of 



Rubber 510 



The Mineral Resources of the United States. By 



J. W. G 5" 



Airship Flights 512 



Mathematics and Physics at the British Associa- 



tion 513 



Chemistry at the British Association 517 



Geology at the British Association 520 



University and Educational Intelligence 521 



Societies and Academies 5^' 



Diary of Societies 522 



