i68 



NA TURE 



\June 14, 1888 



Paris. 

 Academy of Sciences, June 4. — M. Janssen, President, in 

 the chair. — On the equilibrium of a heterogeneous mass in 

 rotation, by M. H. Poincare. This is a generalization (worked 

 out on a fresh basis) of M. Hamy's theorem of fluids in rotation. 

 If all the surfaces of the several liquid layers in contact were 

 ellipsoids, then all these ellipsoids would be homofocal, which 

 is impossible unless all the layers be assumed of equal density. 

 — On the rainbow, by M. Mascart. The results are here 

 published of the author's researches on this phenomenon in 

 connection with M. BoitePs recent communication on the 

 supernumerary arcs of the rainbow. — Experimental researches 

 on the action of the brain, by M. Brown- Sequard. The ex- 

 periments with rabbits here described tend to show that the 

 so-called motor centres and the other parts of one hemisphere 

 of the encephalon may determine movements in both sides of the 

 body through the influence of gravitation alone. This con- 

 clusion, while opposed to the generally accepted doctrines, is in 

 harmony, with the views advocated by M. Brown-Seqnard in 

 previous communications to the Academy. It is evident, he 

 remarks, that the motor zone of each side of the brain is 

 capable of producing movements in the corresponding members 

 on either side, and not, as is commonly supposed, on that side 

 alone which is opposed to the centre of irritation. — Observations 

 of Sawerthal's comet made at the Observatory of La Plata with 

 the Gautier cr2i7m. equatorial, by MM. Beuf, MacCarthy, 

 Salas, and Delgado. These observations cover the period from 

 March 9 to April 2, 1888, and the position of the Observatory 

 is given at lat. - 34 54' 3o"*3, long. W. of Paris 4I1. om. 58s. 

 — Determination of the ohm by M. Lippmann's electrodynamic 

 method, by M. H. Wnilleumier. The true value of the ohm as 



worked out by this process is given by the relation — - — , the 



R 



resistance of the conductor between two given points A and B 

 being R = 0*301889 . io 9 . The value thus obtained is repre- 

 sented by the resistance at o° of a column of mercury with 

 section immq. and length 106 '27cm. — On electro-chemical radio- 

 phony, by MM. G. Chaperon and E. Mercadier. By the 

 method here adopted, the authors have succeeded in obtaining 

 an electro-chemical radiophone whose effects are analogous to 

 those of the selenium electric instruments, possessing equal 

 intensity and being capable of like applications. — On the action 

 of the alkaline phosphates on the alkaline earthy oxides, by 

 M. L. Ouvrard. The author has made a comparative study of 

 baryta, lime, and strontian. for the purpose of determining the 

 nature of the compound substances that may be obtained by 

 fusion of these bases and some of their salts with the alkaline 

 phosphates. — On some new gaseous hydrates, byM. Villard. To 

 those already known the author now adds analogous hydrates of 

 methane, ethane, ethylene, acetylene, and protoxide of nitrogen. 

 They are generally less soluble, less easily liquefied, than those pre- 

 viously obtained, and are decomposed at the respective tempera- 

 tures of 2i 0, 5, 12 , i8°*5, 14°, and 12 . It is shown in the case of 

 methane and ethylene that a gas may form a hydrate above its 

 critical temperature of liquefaction, and that these two gases 

 have a critical temperature of decomposition considerably higher 

 than the others. — Contribution to the study of the ptomaines, 

 by M. Oechsner de Coninck. Having recently obtained a 

 ptomaine in C 8 H n N, the author here determines by analysis a 

 certain number of salts, and describes the preparation of the 

 chloromercurates and iodomethylate. — On the development of 

 the grain of wheat, by M. Balland. It results from these studies 

 that wheat may be advantageously reaped eight or ten days 

 earlier than is customary. During this latter period the grain 

 ceases its independent growth, and may continue to complete its 

 development just as well in the cut ear as on the standing stalk. 

 The point is obviously of great importance to growers, who have 

 thus so much more time to harvest their crops. — Influence of 

 the organic temperature on convulsions produced by cocaine, by 

 MM. P. Langlois and Ch. Richet. Some experiments are 

 described tending to show that the higher the temperature of the 

 animal the more susceptible it becomes to the toxic effects of 

 cocaine. It is inferred that refrigeration should be a general 

 method apt to diminish the effects of toxic substances causing 

 convulsions. — On the chemical action and vegetative alterations 

 of animal protoplasm, by M. A. P. Fokker. Continuing his 

 already-described experiments, the author here shows that, 

 besides the property of producing fermentations, protoplasm pos- 

 sesses that of undergoing vegetative changes, thus confirming his 

 already expressed opinion that the formation of hematocytes is a 

 case of heterogenesis. 



Stockholm. 



Royal Academy of Sciences, June 6. — A review of the 

 researches on the electricity of the air, by Prof. Edlund. — Re- 

 searches on the elasticity and tenacity of metallic wires, by Da 

 Isberg. — On the probability of finding large numbers in the 

 development of irrational decimal fractions and of continued 

 fractions, by Prof. Gylden. — Researches on a non-linear 

 differential equation of the second order, by the same. — On the 

 forms and varieties of the common herring, by Prof. F. A. 

 Smitt. — On the integration of the differential equations in the 

 N body, problem iv. , by Prof. Dillner. — New remarks on the 

 genus Williamsonia, by Prof. A. G. Nathorst. — Contributions to 

 the knowledge of the hydroids of the western coast of Sweden, 

 by M. Segerstedt. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Poems in the Modern Spirit : C. Catty (Scott). — Rural Water Supply : 

 C. L. Hett (Spon). — Contribution a la Meteorologie Electrique, Notes : 

 Prof. J. Luvini (Turin). — Natural History Transactions of Northum- 

 berland, Durham, and Newcastle-upon-Tyne, vol. ix. Part 2 (Williams 

 and Norgate). — Morphologisches Jahrbuch, 13 Band, 4 Heft : C. Gegen- 

 baur (Williams and Norgate). — Bulletin of the New York State Museum of 

 Natural History, No. 3 (Albany). — Rapport Annuel surl'Etat de l'Observa- 

 toire de Paris, 1887 (Gauthier-Villars, Paris). — Archives Italiennes de 

 Biologie, Tome 9, Fasc. 3 (Loescher, Turin). — Zeitschrift ftir Wissenschaft- 

 liche Zoologie, 46 Band, 3 Heft (Williams and Norgate). — Botanische 

 Jahrbiicher, Neunter Band, 5 Heft (Williams and Norgate). — Geological 

 Magazine, June (Triibner). — Journal of the Society of Telegraph-Engineers 

 and Electricians, No. 73 (Spon). — Proceedings of the Bath Natural History 

 and Antiquarian Field Club, No. 3, vol. vi. (Bath). — Hand-book of the 

 Amaryllideae : J. G. Baker (Bell). — Elementary School Atlas : J. Bartholo- 

 mew (Macnillan). — A Season in Sutherland : J. E. Edwards-Moss (Macmil- 

 lan). — The Encyclopaedic Dictionary, vol. vii. Part 1 (Cassell). — Teoria 

 Elemental de las Determinantes : F. Amoretti and C. M. Morales (Biedma. 

 Buenos Ayres). — The Clyde from its Source to the Sea: W. J. Millar 

 (Blackie). — General Physiology: Dr. J. G. M'Kendrick (MacLehose, Glas- 

 gow). — An Illustrated Manual of British Birds, Part 3 : H. Saunders (Gurney 

 and Jackson). — Die Natiirlichen Pflanzenfamilien, 18 and 19 Liefg. : 

 Engler and Prantl (Leipzig). — Ueber Kern- und Zelltheilung i<n Pflanzen- 

 reiche (Heft 1 of Histologische Beitrage) : E. Strasburger (Fischer, Jena). 

 — Sea-side and Way-side Nature Readers, No. 2 : J. M. Wright (Heath, 

 Boston). — Report on a Part of Northern Alberta and Portions of Adjacent 

 Districts of Assiniboia and Saskatchewan : J. B. Tyrrell (Dawson, Montreal). 

 — The Forest Flora of South Australia, Part 8 : J. E. Brown (Adelaide). — 

 Journal of the Chemical Society, June (Gurney and Jackson). 



CONTENTS. page 



The Boys' "Yarrell." By Prof. Alfred Newton, 



F.R.S 145 



Theory and Use of a Physical Balance 146 



The Flora of West Yorkshire 147 



Our Book Shelf :— 



Mitchell: " A Manual of Practical Assaying " . . . 148 



Jones : " Asbestos, its Production and Use " . . . . 14S 



Seidel : " Industrial Instruction " 148 



Letters to the Editor : — 



Electric Fishes in the River Uruguay.' — Dr. P. L. 



Sclater, F.R.S 148 



The Salt Industry in the United States.— F. Tucker- 

 man 148 



Prof. Greenhill on "Kinematics and Dynamics." — 



Prof. J. G. MacGregor 149 



Further Use of Ptolemy's Theorem (Euclid, VI. D) 

 for a Problem in Maxima and Minima. ( With 



Diagram.) — E. M. Langley 149 



Davis's "Biology." — The Reviewer 149 



M. Faye's Theory of Storms. {With Diagram.) By 



E. Douglas Archibald 149 



The Visitation of the Royal Observatory 153 



Industrial Training 155 



Weismann on Heredity. By P. Chalmers Mitchell 156 

 Imperial Geological Union. By Sir J. Wm. Dawson, 



K.C.M.G., F.R.S 157 



Notes 158 



Astronomical Phenomena for the Week 1888 



June 17-23 161 



Geographical Notes 161 



Our Electrical Column 161 



Wheat Cultivation. By Prof. John Wrightson . . 162 



University and Educational Intelligence 163 



Scientific Serials 164 



Societies and Academies 165 



Books, Pamphlets, and Serials Received 168 



