48 



NATURE 



{May 9, 1889 



Survey Memoir on North Wales, the relations of the geo- 

 logical and physical features of Cader Idris have been pointed 

 out in some detail. The present paper dealt with the nature of 

 the eruptions that took place in this area, and the characters of 

 their products at successive stratigraphical horizons. — Discussions 

 followed the reading of both of these papers. 



Paris. 



Academy of Sciences, April 29. — M. Hermite in the 

 chair. — On a means of obtaining photographs of true chromatic 

 value by the use of coloured glasses, by M. G. Lippmann. By 

 the judicious employment of green, yellow, and red glass in the 

 way here explained, excellent results have been obtained even 

 with present plates, notwithstanding their greater sensitiveness 

 to blue. The impressions are described as clear and free from 

 brown patches, the green foliage, the red or yellow draperies, 

 instead of yielding brown tints, being reproduced in delicately 

 modelled design as in a well-executed engraving. — Loss and gain 

 of nitrogen as determined by the experiments carried on at 

 Grignon from 1875-89, by M. P. P. Deherain. A general 

 survey of the results of these experiments leads to the conclusion 

 that all soils containing considerable quantities of nitrogen in 

 combination, say two grammes to the kilogramme, lose, if culti- 

 vated without manure, far more nitrogen than is absorbed by 

 the crops, but in proportions varying according to the nature 

 of those crops — more with beetroot, less with maize grown for 

 fodder, still less with potatoes and wheat. But when the 

 ground has thus been impoverished, no longer containing more 

 than I '45 or i "50 grammes to the kilogramme, the losses ceases 

 and the ground begins, on the contrary, to recover a certain 

 proportion of nitrogen, the gain being much greater on grass- 

 grown than on tilled lands. — Underground growth, seed, and 

 affinities of the Sigillaria, by M. Grand'Eury. The author, who 

 has had a favourable opportunity of studying these fossil plants 

 in the Carboniferous formations of the Gard, confirms the view 

 always held by Prof. Williamson, that they are true Cryptogams 

 of the vascular order, despite the radiated structure of the wood. 

 But they are not directly connected with any living type, and 

 form a family of fossil plants which entirely disappeared towards 

 the close of the Palaeozoic period. — Two eruptions observed on 

 the sun in September 1888, by le Pere Jules Fenyi. These 

 eruptions, observed on September 5 and 6, are described as of 

 an extremely violent character, and as all the more remarkable 

 because occurring at the epoch of minimum intensity. Both 

 appear to have taken place about the same region of the solar 

 ■disk, and the protuberance accompanying the first contained 

 the vapours of several metals, such as sodium, barium, and 

 iron, besides two very bright red rays of an unknown 

 ■element, one between B and C, the other between B and 

 .a. — On the alloy of the standard international kilogramme, 

 by M. J. Violle. The alloy of platinum and iridium in 

 the proportion of 10 per 100, prepared with the greatest care by 

 M. Matthey, is here found to be still somewhat defective. M. 

 Violle's researches show that an alloy of 9 parts platinum and i 

 iridium yields more uniform and accurate results both as regards 

 density and specific heat. The density thus obtained is an 

 absolute constant, incapable of further modification under cold- 

 hammering, annealing, or any other severe test. — Dilatation and 

 compression of carbonic acid, by M. Ch. Antoine. In a previous 

 note (January 21, 1889), the author showed that the reciprocal 

 of the coefficient of dilatation under constant pressure is given 

 by the relation — 



)8 = ^^ - /., 

 5 



5 being a constant coefficient, ts and Vs the temperature and 

 volume at saturation under the pressure /. Here he finds that 

 more simple values may be obtained both for pVs and &. — On 

 electrolytic polarization by metals, by M. N. Piltschikoff. A 

 general result of these researches is that one metal may be polar- 

 ized by another. — On the formation of earths containing nitrogen, 

 by MM. A. Miintz and V. Marcano, The authors describe 

 numerous caves in Venezuela, both on the coast ranges and on 

 the slopes of the Andes, which contain vast deposits richly 

 charged with nitrates and interspersed with the remains of large 

 extinct animals. The bones are so friable that they crumble to 

 dust at contact of the finger ; hence the difficulty of determining 

 the species. They consist almost exclusively of phosphate of 

 lime ; carbonate of lime is entirely absent, and there are but 

 slight traces of organic matter. In these caves, sheltered from 



the action of rain-water, the nitrogen yielded by the nitrified 

 organic remains was gradually accumulated. In some places the 

 beds are over 30 feet thick, containing from 4 to 30 per 100 of 

 nitrate of calcium, and from 5 to 60 of phosphate of calcium. — On 

 the art of utilizing statistics, by M. Delauney. With a view to the 

 better utilization of statistical returns, especially in the sphere of 

 meteorology, the author here proposes a solution of the problem : 

 Given the statistics of a phenomenon, to find a certain method 

 by means of which the laws controlling that phenomenon may 

 be discovered. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Sylvan Folk: J. Watson (Unwin).— Moral Order and Progress: S- 

 Alexander (Triibner). — Physiological Notes on Primary Education : M. P. 

 Jacobi (Putnam).— Die Meteorologie Ihrem Neuesten Standpunkte Gemass 

 und Mit Besonderer Berucksichtigung Geographischer Fragen : Dr. S. 

 Giinther (Miinchen, Ackermann). — Report of Rainfall in Washington Terri- 

 tory, &c., for two to forty years (Washington).— Haunts of Nature : H. W. 

 S. Worsley-Benison (Stock).— A Table of Specific Gravity for Solids and 

 Liquids (Constants of Nature, Part i) : F. W. Clarke (Macmillan).— Half a 

 Century of Australian Progress : W. Westgarth (Low).— Electric Light for 

 the Million : A. F. Guy (Simpkin).— A Syllabus of Modern Plane Geometry : 

 (Macmillan). — Geological Magazine, May (Triibner).— Annalen der Physik 

 und Chemie, 1889, No. 5 (Leipzig, Barth). — Quarterly Journal of Micro- 

 scopical Science, May (Churchill).— Proceedings of the Royal Society of 

 Edinburgh, vol. xv. No. 128. — Proceedingsof the Royal Society of Edinburgh, 

 Session 1888-89, vol. xvi. pp. 65-128. — Journal of Physiology, April (Cam- 

 bridge). — Meteorological Record, vol. viii. No. 31 (Stanford). — Quarterly 

 Journal of the Royal Meteorological Society, January (Stanford).— Quarterly 

 Weather Report, Part 4, October-December, 1879 (Eyre and Spottiswoode). 

 — Hourly Readings, 1886 (Eyre and Spottiswoode). 



CONTENTS. PAGE 



The Estate of Her Majesty's Commissioners of 



1851 25 



Warren de la Rue 26 



The Philosophy of Mysticism 28 



Our Book Shelf:— 



Roscoe and Schorlemmer : " A Treatise on Chemistry " 31 

 Smith : " Solutions of the Examples in a Treatise on 



Algebra " 31 



Low: " Applied Mechanics " 31 



Yate : " Northern Afghanistan " 31 



Knight: " By Leafy Ways" 32 



Letters to the Editor: — 



On an Electro-magnetic Interpretation of Turbulent 

 Liquid Motion. — Prof. Geo. Fras. Fitzgerald, 



F.R.S 32 



The New Eruption of Vesuvius. — Dr. H. J. Johnston- 



Lavis 34 



The Sailing Flight of the Albatross. — Lord Rayleigh, 



F.R.S 34 



"Giphantia"— Sir J. D. Hooker, F.R.S 34 



Geological Photography. — Osmund W. Jeffs ... 34 

 Columnar Structure in Ice. — T. D. La Touche ... 35 

 Brilliant Meteor. — Captain T. Herbert Clarke, 



RV 35 



A New Mountain of the Bell. — H. Carrington 



Bolton 35 



Klein's " Ikosahedron " 35 



The Northfleet Series Electric Tramway. {Illus- 

 trated.) . • , , 39 



The Examinations for Woolwich and Sandhurst . . 43 



Notes 44 



Astronomical Phenomena for the Week z88g 



May 12-18 46 



Geographical Notes 46 



The Liverpool Marine Biology Committee's Easter 



Dredging Cruise. By Prof. W. A. Herdman ... 47 



Societies and Academies 47 



Books, Pamphlets, and Serials Received 48 



