4o8 



NATURE 



\Sept. 12, 1872 



the rocking arms liave been finally reduced to liai'dened steel 

 pins of small diameter, and so mounted that their motions, when 

 of small range, should be roUin|T not sliding motions, and great 

 delicacy is tlius obtaineil. The centre of gravity is brought to 

 within o'oo65 in. of the axis of suspension, and the time of a 

 single swing is over thirty-five seconds. Yet so great is the 

 delicacy of the suspension, a weight of Tj^s'injir part of that of 

 the wheel itself, if placed at its extreme radms, will produce an 

 oscillation of i}in, in range, and which will continue for m.any 

 minutes ; or if the wheel be moved 90° from its position of rest, 

 the oscillations will continue for nearly twenty minutes, the 

 movement being so slou' and solemn as to impress on the mind 

 of an observer who had not seen it put in motion tliat the action 

 was self-originated, or induced by some mysterious agency. 

 The oscillation of a ship can scarcely communicate any motion 

 at all to the wheel, and any minute rotation which is, in fact, 

 communicated will assume the form of an oscillation, having so 

 long a " period" that its effects will be easily separable from 

 those proper to the oscillation of the ship. Thus the indications 

 will be more exact than those produced by the rocking arm on 

 deck. This improved apparatus has not yet been tried, but is 

 ready, waiting a suitable d.ay for trial on board a ship at Ply- 

 mouth. 



Mr. Froude stated that though the apparatu^he had described 

 was purely his own invention, it had interested him greatly to 

 learn recently that an arrangement substantially identical with 

 that combinatioiiiwhich he first described had about two years 

 previously been invented and successfully used by an able 

 French naval architect (M. Bertin, of Cherbourg), with whom, 

 partly in virtue of this circumstance, it has since been his good 

 fortune to become acquainted and to correspond. It was, how- 

 ever, a satisfaction to him that he was at the present time ahead 

 of his friendly competitor in the race, so far as regarded the 

 delicately-hung heavy fly-wheel which was to furnish an auto- 

 matic constant record of the angles or absolute rolling or devia- 

 tions from the horizontal assumed at ea;h moment by the ship. 



SOCIETIES AND ACADEMIES 



P.\RIS 



Academy of Sciences, Aug. 5. — Prof. Cayley pre;ented a 

 memoir on Orthogonal Surfaces. — M. E. Becquerel communi- 

 cated a spectroscopic analysis of the light emitted by the phos- 

 phorescent uranium compounds. — M. Daubree jsresented a note 

 on the discovery of a second meteorite, which fell on the 23rd of 

 July last, in the canton of St. Amaud (Loir-et-Cher). This 

 appears to have formed part of the fall noticed at the meeting 

 of the Academy on July 29. — A long letter, illustrated with 

 figures, from Father Secchi, on the solar eruption observed on 

 July 7, and on the phenomena which accompanied it, w^as com- 

 municated. In this paper the author referred to the phos- 

 phorescent light emitted by certain animals, and upon this subject 

 MM. de Quatrefages, Milne-Edwards, and E. Becquerel made 

 some remarks. — ]\I. Dumas read an important memoir on alco- 

 holic fermentation, and a note on the ferments belonging to the 

 dias'ase group. — MM. Favreand Valson presented a continuation 

 ot their researches upon crystalline dissociation. — M. G. Ville 

 presented a memoir on the quick quantitative determination of 

 phosphoric acid. —A note by M. Houzeau, on the decolorising 

 power of concentrated ozone, was read, and upon this M. P. 

 Thenard made some remarks. — M. Wurtz presented a note by 

 M. E. Grimaux, on some derivations of tetrachloride of naphtha- 

 line. — A note was read by M. Sirodot on a bone-deposit situated 

 at the foot of Mont Dol, containing bones and teeth of elephant, 

 horse, ox, rhinoceros, and other mammals, generally broken and 

 often calcined, with a few fragments of flints and at least one 

 stone implement. — M. C. Sainte-Claire DeviUe presented a note 

 by M. Gorceix, containing a summary of the phenomena pre- 

 sented by the volcano of .Santorin at the close of the eru]ition 

 of ib66, or from December 1S69, to October 1S71. — M. T. 

 Lesliboudois presented a note on what he calls heterogeneous 

 Dicotyledons, or those which do not produce their new tissues 

 exclusively in the generative zone between the wood and the bark. 

 — M. Duchartre communicated a note by M. J. Duval fouve on 

 a form of epidermic cell which appears to be peculiar to the Cyper- 

 acea;. — M. de Quatrefages read a memoir on the Mincopies and 

 the Negrito race in general, containing a discussion of the charac- 

 ters of the Andaman islanders, and of their relations to the other 

 black races of man. — M. Blanchard presented a note by M. J. 



Kunckel on the development of the striated muscular fibres in 

 insects, in which the author maintains that the primidve element 

 of the muscle is a cell, which, by its elongation, forms ihe fibrilla, 

 the fibre or primitive bundle being a secondary formation. — M. 

 Blanchard also communicated a note by M. .\. TiUot on the 

 embryonic form of the Hairworms {Gordius), in which the de- 

 velopment of those parasites from the egg is descr b 'd, and they 

 are shown to pissess, in the embryonic state, some analogy 

 with the Ecldiioi hynchi. — A note by M. J.Gerbe on the formation 

 of the adventitious products of the ovum of the Plag ostomi was 

 presented by M. C. Robin. 



August 12. — Prof. Cayley communicated a continuation of his 

 memoir on orthogonal surfaces. — VI. Vvon VilUrc^au presented 

 a further memoir on the applications of his new theorem of 

 general mechanics to the equilibrium of yase.s. — General Morin 

 presented a report upon a memoir by M. Graeff, on the action 

 which the breakwater of Pinay exerts upon the floods of the 

 Loire at Roanne. — A note on the vibrations of cords and rods in 

 liquid.s, by M, E. Gripon, was read. — M. Pasteur presented a 

 note, by M. E. Branly, on the measurement of the intensity of 

 currents by means of the electrometer. — A note, by M. Broun, 

 on magnetic variations observed at Trevandrum during the 

 eclipse of December 11, 1S71, was presented; as also a note 

 containing observations of meteors at various sations on August 

 9, 10, and II, by MM. Le Verrier and Wolf. — A short note on 

 the observations relating to presence of magnesium in the chro- 

 mosphere of the sun, by M. Tacchini, .was transmitted by M. 

 Faye. — MM. Favre and Valson presented the continuation of 

 their thermo-chemical researches upon crystalline dissociation. — 

 M. Berthelot presented a note on the partition of a base between 

 several acids in solutions, in which he treatei of the monobasic 

 acids ; and M. Pasteur communicated a note, by M. E. Jung- 

 fleisch, on the conversion of right tartaric acid into racemic acid 

 by exposure to heat in the presence of water. — M. Dumas called 

 attention to some researches, by M. Latimau, on Pliylloxcni vns- 

 talrix. — M Brongniart presented a detailed report upon a most 

 important memoir, by M. Grand-'Eury, on the Carboniferous 

 flora of the Department of the Loire. 



BOOKS RECEIVED 



Foreign.— Through Williams : 

 3 vols. : Karl IJruhns. — Eludes si: 

 celles de I'hommc : J. C. Houzeau, 

 Theorie mccaniiuic dc la chaleiir 



nd Norgats — Alexander von 

 r les Facultes des ammaux 

 2 voh.— Ocuvrcs desVcrdet, 

 ; E. Verdet, Vol, i. and Vol 



Humboldt, 

 compares li 



Americ.in.— Report of the Palaiontolosy of E.HStern Nebraska : T. B. 



CONTENTS Pagk 



The Potato Dise.^se 389 



Sharpe and Dkksser's Birds of Europe 390 



Geometrical Conic Sections ^91 



Our Book Shele 391 



Letters to the Editor : — 



The Variation in Outline of American "Flint" Arrow Heads.— 



Prof Chas. C. Abbott ' ... 392 



Millionsof Millions.— A. CoWper Ranyard, F.R.A.S 393 



Ferlilisation by Moths.— W. C. Marshall 3Q3 



Orijin of Insects.-Ur. F. Buchanan White, F.LS 393 



Solar Spols.—W. F. Denning, F.RA.S 303 



Correlaiioii of Colour and Music. — G.C.Thompson 393 



Cat's Teeth.— R. Lvddekker 394 



Danish Expedition to the.Faroes By Dr. Rudv. Wille.moes- 



SUHM 394 



Natural History Education at Harvard University . . . 394 



Melting AND Regelation OF Ice. ByJ. Aitken 396 



A Gigantic Pleasuring Ground; The Yellowstone National 



Park OF the United States. {JVitk llhtstrations) 397 



Notes ^-ji 



The British Association Meeting : — 



Section A — Sectional Proceedings 402 



Section B.— Sectional Proceedings 404 



Section C. — Sectional Proceedings 406 



Section D. — Sectional Proceedings 406 



Section G.— Sectional Proceedings . .\ 407 



Societies and Academies 40S 



Books Received 408 



Errata.— Vol. vi., p. 382, 

 read " graptolites : " lir e 20. 

 " Dkty,Kra/<ti,s' re.ad •'Die. 

 '• Plilosrtif'tus .■■' line 35, for ■ 



n C, Geology, line -, for " graptolltc " 

 '■. serrus" read " T. scr,;i :" line 25. for 

 ■tHs; • line )i, for " l'/i}'il,<i;r,i/t„s " read 

 read "two." 



