4o6 



NA rURE 



[Feb. 24, 1887 



fogs, and even rain. Hence the strong tensions of atmospheric 

 electricity so frequently signalled from the New York Observa- 

 tory some days before the arrival of storms and wet weather on 

 the west coast of Europe. During thirty-six years of constant 

 study, the author has recorded thousands of similar observations, 

 which have been overlooked by physicists dazzled by theories 

 opposed to the natural conditions. — Further remarks on the 

 question whether electricity is developed during the condensa- 

 tion of aqueous vapour, by Prof. Costantino Rovelli. In reply 

 to the statements of Prof. Magrini, the author points out that, 

 although his own experiments may have their weak side, the 

 prolonged and repeated observations of Prof. I'almieri cannot 

 be refuted by merely negative proofs. 



SOCIETIES AND ACADEMIES 

 London 

 Physical Society, February 12. — Annual General Meet- 

 ing. — Prof. B. Stewart, F. R.S., President, in the chair. — In 

 opening the proceedings the President regretted that in their 

 Report the Council have to record the loss of one who took a 

 prominent part in the proceedings of the Society, the late Dr. 

 Guthrie. It was, however, satisfactory to learn that the appeal 

 of the Guthrie Memorial Committee, under the presidency of 

 Prof. Huxley, had been generously responded to. The Council 

 also learn with regret from Dr. E. Atkinson that owing to pres- 

 sure of work he is unable to retain the office of Treasurer to the 

 Society, and desire to express their thanks to him for his past 

 services. Prof Riicker has consented to be nominated for the 

 office thus rendered vacant, and the Council believe that by his 

 election the connection between the Society and the Normal 

 School of Science (which is so desirable) will be maintained. — 

 The Report of the Council for the year 1S86 was read and received, 

 and the following gentlemen were elected iSIembers of the Council 

 for the present year: — President : Dr. Balfour Stewart, F.R.S. ; 

 Vice-Presidents : Dr. E. Atkinson, Prof. W. E. Ayrton, F.R.S. , 

 Shelford Bidwell, F.R.S., Prof. H. McLeod, F.R.S. ; 

 Secretaries: Prof. A. W. Reinold, F.R.S., Walter Baily ; 

 Treasurer: Prof. A. W. Riicker, F.R.S.; Demonstrator: 

 C. V. Boys ; other Members of Council : R. H. M. Bosanquet, 

 W. H. Coffin, Conrad W. Cooke, Prof. G. Forbes, Prof. 

 F. Fuller, Prof. J. Perry, F.R.S., W. N. Shaw, Prof S. P. 

 Thompson, C. M. M^hipple, C. R. Alder Wright, F R.S.— 

 The President proposed the following resolution : " That at the 

 end of Clause I r of the By-laws, which says, ' Every candidate 

 for admission into the Society shall be recommended by not less 

 than three members, to two of whom he must be personally 

 known,' there be added, 'When a candidate living abro.ad is a 

 member of a recognised scientific Society, such membership may, 

 subject to the approval of the Council, be held equivalent to 

 the personal knowledge aforesaid.' " The resolution was carried, 

 subject to confirmation by a special general meeting to be held 

 on February 26. — A vote of thanks, proposed by Prof. Ayrton 

 and seconded by Prof. McLeod, to the Lords of the Committee 

 of Council on Education, for the use of the rooms and apparatus 

 of the Normal School of Science, was passed unanimously. — 

 The Hon. R. Abercromby proposed a vote of thanks to the 

 olTicers of the past year for their gratuitous services, which was 

 seconded by Prof. Pickering. — Sir Philip Magnus proposed a 

 vote of thanks to the auditors. Colonel Festing and Prof. Fuller, 

 which was seconded by Mr. Lecky, and passed unanimously. — 

 Mr. J. Brown was elected a Member of the Society. — The follow- 

 ing cr mmunication w.is then read : — Note on the tenacity of 

 spun glass, by E. Gibson and R. E. Gregory. The authors have 

 experimented on the tenacity of glass rods and fibres made from 

 the same piece of glass. The fibres varied from 1/25 to 1/50 

 mm. and the rods from about J to I mm. in diameter. They find 

 the tenacity per square centimetre of rods increases as the diameter 

 decreases, as in ordinary wires, whereas with fibres this is not 

 shown. Experiments were shown illustrating the method of 

 working, and the highest tenacity recorded was for a fibre of 

 •0340 mm. diameter, which gave 466 x 10" dynes per square centi- 

 metre, a value about half as great as that for steel wires. The 

 authors refer to Quincke's suggestion that the increased tenacity 

 of sinall wires is due to surface-tension, and inay be represented 

 by IV = Ad + Bd-, where W is the breaking weight and d the 

 diameter, but their own results with glass do not agree with this 

 formula. Sir Philip Magnus asked if the diameters were 

 measured at the point of rupture, if the elongation was deter- 



mined, and whether the authors were able to suggest any other 

 formula which would express their results. Mr. C. V. Boys 

 remarked that the tenacity being so much afl'ected by accidental 

 circumstances, such as rate of cooling, no such formula could be 

 expected. Prof. Riicker, referring to Quincke's experiments, 

 said that the surface-tensions of metals calculated from them 

 appear improbable. After some further remarks by the President, 

 Prof Ayrton, Mr. C. V. Boys, Prof McLeod, and Mr. Gregory, 

 the proceedings terminated. 



Royal Meteorological Society, February 16. — Mr. W. 

 Ellis, President, in the chair. — The adjourned discussion on the 

 Hon. R. Abercromby 's paper on the identity of cloud forms all 

 over the world, and on the general Jprinciples by which their 

 indications must be read, was resumed ; and the following papers 

 were read : — Remarks concerning the nomenclature of clouds 

 for ordinary use, by Prof. • H. H. Hildebrandsson ; and 

 Suggestions for an international nomenclature of clouds, by 

 by the Hon. R. Abercromby. Both Prof. Hildebrandsson and 

 Mr. Abercromby have paid great attention to the C|uestion of 

 the forms of clouds, and having recently conferred together, 

 they have agreed to recommend for international use the follow- 

 ing ten principal varieties, viz, : — High-level clouds : cirrus, 

 cirro-stratus, cirro-cumulus ; middle-level : strato-cirrus, cumulo- 

 cirrus ; and low-level ; cumulus, stratus, strato-cumulus, nimbus, 

 cumulo-nimbus. — The influence of weather on the proportion of 

 carbonic acid in the air of plains and mountains, by Dr. W. 

 Marcet, F.R.S., and M. A. Landriset. The authors give an 

 account of some experiments which they have made on the pro- 

 portion of carbonic acid in the air at Geneva and on the summit 

 of the " Dole," the highest point of the Jura chain, the differ- 

 ence in altitude being 4193 feet. The results of these experi- 

 ments show : (i) that in tine clear weather on a mountain chain 

 of moderate Alpine altitude, and in the .adjoining valley or 

 plain, the atmosphere holds the same mean proportion of car- 

 bonic acid at both places ; and (2) that when the summit of a 

 mountain chain is in a fog, a circumstance which frequently 

 happens in 'an Alpine district, the air in the fog contains a 

 smaller proportion of carbonic acid than it would hold in fine 

 clear weather. — The Secretaiy, Dr. Tripe, read a letter received 

 from .Sir F. Abel, Organising Secretary to the proposed Imperial 

 Institute, inviting the Society to draw the attention of the 

 Fellows to the undertaking, with the view of their contributing 

 towards it. The President stated that copies of the letter and 

 of the accompanying paper, explanatory of the scheme, would 

 be forwarded to each Fellow. 



Mathematical Society, February 10. — Sir James Cockle, 

 F.R.S., President, in the chair. — The following communica- 

 tions were made : — On the equation of Riccati, by the Presi- 

 dent (Prof. Hart, Vice-President, taking the chair). — The ortho- 

 centroidal circle [i.e. the circle whose diameter is the join of 

 the oithocentre and centroid), by R. Tucker. — On polygons 

 inscribed in a quadric and circumscribed about two confocal 

 quadrics, by R. A. Roberts. — On the binomial equation 

 .v" -1=0; quinquisection, by Prof. Tanner. — Symmetrical 

 determinant-formulfe in elliptic functions, by L. J. Rogers. — 

 Notes on curves, by H. M. Taylor. — Some generalisations of 

 differential formulce connected with the change of the indepen- 

 dent variable in a differential expression, with application to a 

 new class of reciprocants, by C. Leudesdorf. 



Geological Society, February 9. — Prof. J. W. Judd, F.R.S., 

 President, in the chair. — The following communications were 

 read : — Evidence of glacial action in the Carboniferous and 

 Hawkesbuiy series, New South Wales, by T. W. Edgworth 

 David. — The terraces of Rotomahana, New Zealand, by Josiah 

 Martin. — The eruption of Mount Tarawera, by Capt. F. W. 

 Hutton. The paper began with a description of the country in 

 which the eruption took place. From Tongariro to White 

 Island, in the Bay of Plenty, a distance of 130 miles, there 

 extends a belt, 20 or 30 miles wide, abounding in solfataras, 

 geysers, hot springs, &c., and composed of volcanic rocks, chiefly 

 rhyolite, with some augite-andesite. About the middle of this 

 belt lie the mountain and lake of Tarawera, and two or three 

 miles further south Lake Rotomahana, the spot where the famous 

 Pink and White Terraces existed. Before the recent eruption 

 there were no craters on Mount Tarawera, the form of which 

 was a ridge, apparently due to denudation. Having described 

 the eruption, Capt. Hutton briefly noticed the results of the 

 eruption in the form of fissures on Mount Tarawera, the change 

 of Rotomahana from a lake to a crater of larger dimensions. 



