56 



NATURE 



[May 19, 1892 



clouds in the morning of January 30 (Nature, xlv. p, 365), 

 I may add that the same beautiful but as yet mysterious pheno- 

 menon was seen here January 30 and 31, both days in the 

 south-west after sunset. Since the display of December 1885, 

 mentioned by Mr. Backhouse, it has been seen here every year, 

 except 1888, mostly for a day or two in January or February. 



H. Geelmuyden, 

 University Observatory, Christiania, May 3. 



Wave-Propagation of Magnetism. 



In an interesting article in last month's Philosophical Magazine, 

 Mr. Trowbridge has given an account of some experiments made 

 by him with the view of examining for any indication of a definite 

 rate of propagation in the magnetization of iron. In these ex- 

 periments no indication was observed. 



It seems to me, however, that nothing of this sort is likely to 

 be observed where the magnetizing force is as great as that used 

 by Mr. Trowbridge, and that there are two classes of distux'b- 

 ances to be carefully distinguished. For example, in Prof. 

 Ewing's well-known magnetic model, something which looks 

 very like a definite rate is to be seen in the case of a disturbance 

 not sufficiently large to cause toppling over of the " molecule 

 magnets" ; that is to say, to cause the little magnets to pass 

 through their positions of unstable equilibrium. On the other 

 hand, with a larger disturbance the phenomenon visibly partakes 

 of a different character. Here, throughout the medium, there are 

 to be seen at irregular moments what may be considered as cases 

 of precipitation of energy, owing to the occurrence of these 

 positions of unstable equilibrium. 



These two stages should be carefully distinguished, for an 

 essential in wave-propagation as opposed to a rate of precipitation 

 of energy (such as a rate of ignition, &c. ) is obviously that the 

 medium should not be permanently altered. 



In some experiments made by me, very much smaller alternat- 

 ing currents than those used by Mr. Trowbridge were employed. 

 But the occurrence of spurious effects, simulating to a remarkable 

 degree the interference nodes looked for, must have effectually 

 obscured in my experiments the true phenomenon, supposing its 

 existence. So that, considering the conditions of both our ex- 

 periments, I still think the subject requires further investigation 

 before coming to a decision in the matter. Indeed, when larger 

 currents are used, no indication is to be found of even these | 

 spurious effects. 



In Prof. Ewing's model, when the magnets point on the whole 

 the same way (representing a high state of magnetization), the 

 rate of propagation of a small disturbance affords a more definite 

 problem. Tried experimentally, this latter case might afford 

 more satisfactory results. Fred. T. Troutox. 



Correction in " Island Life." 

 In Dr. Merriam's recently published paper on " The Geo- 

 graphical Distribution of Life in North America," an important, 

 and to me almost inexplicable error in my work " Island Life" 

 is pointed out. It occurs at page 41 in the first edition, and 

 is unfortunately repeated at the same page in the recently pub- 

 lished new edition, and consists chiefly in stating that the moles 

 (Talpidse) are almost confined to the Palaearctic region. But a 

 little further on in the same work (page 48 of first edition, and 

 page 49 of second edition) it is correctly stated that there are 

 three peculiar genera of moles in North America, and the same 

 statement is made at page 115, and again at page 190 of vol. 

 ii. of my " Geographical Distribution of Animals." At page 182 

 of vol. i. of the latter work, however, the error first appears, and 

 it is this erroneous passage that has remained unnoticed till now, 

 and was unfortunately repeated in "Island Life." In the 

 same paragraph an error of a similar kind also occurs as to the 

 distribution of the lynxes. To correct these errors pages 41 

 and 42 of the new edition of " Island Life " are being reprinted, 

 and will be sent to all who possess the volume if they will forward 

 a stamped and directed envelope to the publishers. 



Alfred R. Wallace. 



THE INTERNATIONAL CONFERENCE ON 

 CHEMICAL NOMENCLATURE. 



AT the meeting of the International Chemical Con- 

 gress, held in Paris in the summer of 1889, a special 

 Section was appointed to consider the unification of 



NO. 1 177, VOL. 46] 



chemical nomenclature, and, after discussing a variety of 

 propositions, some of which were adopted, it was decided 

 to form an International Commission for the further study 

 of the subject.^ 



The members resident in Paris, having been constituted 

 a permanent committee of the Commission, have devoted 

 an immense amount of time and care to the preparation 

 of a scheme, and it was to discuss their report -^ that we 

 met at Geneva on Easter Monday last. The French 

 Committee had issued invitations, not only to members 

 of the Commission, but also to many other prominent 

 chemists, so that the meeting was a thoroughly repre- 

 sentative one. It is worth mentioning, as an illustration 

 of the sympathetic treatment accorded by public bodies 

 in France to men of science, that the Paris- Lyons-Mar- 

 seilles Railway Company granted a reduction of one-half 

 on the fare over their line to members of the Congress. 



Very happily, the local committee had arranged that 

 all might stay at the one hotel — the Mctropole— and it 

 was here that we first met in friendly union on the Monday 

 evening.-' The next morning the Congress assembled at 

 the Hotel de Ville, M. Richard, the Cantonal Minister 

 of Education, being in the chair. After an admirable 

 address of welcome from this gentleman, who appeared 

 to thoroughly appreciate the importance of the object in 

 view, on the motion of Prof. Cannizzaro it was wisely 

 decided not to follow the compHmentary, but somewhat 

 unbusinesslike, Continental practice so frequently adopted, 

 of appointing a different chairman each day, but to have 

 only one. M. Friedel, who had taken the chair at all the 

 numerous meetings of the Paris Committee, having been 

 chosen by acclamation President of the Conference, 

 formal business was at once entered into, and, after the 

 necessary interval for lunch, the sitting was resumed in 

 the afternoon. We met in like manner on the two 

 following days, and the final sitting took place on the 

 Friday morning, but many had left before this. On Tues- 

 day evening, by invitation of the local committee, we visited 

 the theatre, a very beautiful building. On the Wednesday 

 evening, we were entertained by them at a dinner at the 

 Hotel Metropole, on which occasion a very striking 

 speech was delivered by Prof, von Baeyer, who, after point- 



' The followine chemists eventually consented to serve on the Com- 

 mission: — MM. B(5hal, Berthelot, Bouveault, Combes, Fauconnier, Friedel, 

 Gautier, Grimaux, Jungfleisch, Schutzenberger (all representing France), 

 Graebe (Switzerland), Alexejeff and Beilstein (Russia), von Baeyer and 

 Nolting (Germany), Lieben (Austria), Paterno (Italy), Franchimont 

 (Holland), Armstrong (England), Istrati (Roumania), Calderon (SpainX 

 Cleve (Sweden), Boukowski-Bey (Turkey), Ira Remsen (United States), 

 and Mourgues (Chili). 



'■' This report had been prepared by the following : — MM. Friedel 

 (President). B^hal, Bouveault, Combes, Fauconnier, Gautier, and Grimaux. 



•" The following is the official list of those who took part in the Conference : 

 —MM. H. E. Armstrong, professeur a la Central Institution, Londres, 

 secretaire de la Chemical Society ; A. Arnaud, professeur au Mus6uni, a 

 Paris ; Adolphe von Baeyer, professeur a I'Universiti^ de Munich ; Barbier, 

 professeur a la Faculty des sciences de Lyon; Aug. Behal, professeur a 

 I'Ecole sup<irieure de pharmacie de Paris; Louis Bouveault, docteur es 

 sciences, Paris ; Stanislas Cannizzaro, professeur a I'UniversittS de Rome ; 

 Paul Cazeneuve, professeur a la Faculty de medecine de Lyon ; Alphonse 

 Combes, docteur es sciences, Paris ; Alphonse Cosso, directeur de la Station 

 expirimeniale d'agriculture, a Turin; Maurice De Lacre, professeur a. 

 I'Universite de Gand ; Michel Fileti, professeur a TUniversit^ de Turin; 

 Emile Fischer, professeur a I'Universite de Wiirzbourg ; A.-P.-N. Franchi- 

 mont, professeur .\ I'Universite de Leide ; Charles Friedel, membre de 

 I'Institut, professeur a la Sorbonne. Paris ; Dr. J. H. Gladstone, F.R.S., 

 Londres ; Carl Graebe, professeur a I'Universite de Geneve ; Philippe- 

 Auguste Guye, professeur a I'Universite de Geneve ; Istrati, professeur a 

 I'Universite de Bucarest ; Albert Haller, professeur a la FacuUe des sciences 

 de Nancy; Maurice Hanriot, professeur agrege a la Faculte de medecine^ 

 Paris; A.-R. Hantsch, professeur .\ I'Ecole polytechnique de Zurich; 

 Achille Le Bel. docteur es sciences, a Paris ; A. Lieben, professeur a 

 I'Universite de Vienne ; L^on Maquenne, docteur es sciences, aide-naluraliste 

 au Museum, Paris : von Meyer, professeur a I'Universite de Leipzig ; Denis 

 Monnier, professeur a I'Universite de Geneve; R. Nietzki, professeur a 

 I'Universite de Bale ; Emilio Noelting, directeur de I'Ecole de chimie de 

 Mulhouse ; Emmanuel Paterno, professeur a I'Universite de Palermo ; 

 Ame Pictet, privat-docent a I'Universite de Geneve; William Ramsay, 

 F.R.S., professeur a TUniversite de Londres ; Zdenko-H. Skraup, 

 professeur a I'Universite de Graz ; Ferdinand 'Tiemann, professeur a 

 I'Universite de Berlin. _ t. •, aj 



Le Comite local d'organisatlon .se composait de : — MM. Emile Ador, 

 H.-W. de Blonay, Alex. Claparede, Professeur C. Graebe, Professeur Ph. -A. 

 Guye, Alex. Le Royer, Professeur Denis Monnier, Ame Pictet, Fred. 

 Reverdin, Professeur Albert Rilliet, Edouard Sarasin. 



