664 



NATURE 



raised to incandescence and fire the gas mixture 

 around them. This involves the assumption that an 

 amount of combustible gas, which is insufficient to 

 propagate flame in the mixture, can by suffering 

 partial combustion bring the remainder into an exolo- 

 sive state. The heating up of a gas mixture by an 

 external source of heat increases its explosive power- 

 but this IS not found to be true if the heat is derived 

 .rom the burning of the gas itself. The authors have 

 heated up mixtures of coal gas and air and mixtures 

 of methane and air by means of a long platinum 

 spiral through which an electric current wjpassed 

 After chemical combustion is started the mixtures 

 become les^ and not more explosive, although only a 

 TI^TJ^ %' ^'% is derived from combustion of the 

 gas Itself. Even if the incombustible dusts acted like 

 platinum it would be difficult to explain Abel's results 

 as being due to a catalytic action. Experiments ear- 

 ned out at Eskmeals show that the presence of fine 

 incombustible dusts does not increase, but retards the 

 rate of explosion of gaseous mixtures. 



Edinburgh. 

 Royal Society, January 2o.-Dr. B. N. Peach 

 Th • ■^'I'^e-president, in the chair.— J. jM'Lean 

 Thompson : Studies in floral zygomorphy. I The 

 initiation of staminal zygomorphy. A study of the 

 very young buds and expanded ' ffowers of' Gregil 

 i>iUherlandn showed that in all the parts of the flower 

 zygomorphy was initiated, but it was not maintained. 

 In the case of the stamens the filaments did not attain 

 he maximum length simultaneously; but sooner or 

 ater they all attained the maximum "length, and when 

 this stage was reached the anthers dehTsced. It was 

 shown that the lengthening of the filaments was due 

 to the elongation of the cells, the number of which 

 remained the same from an early development stacre 

 up to the perfected condition.-lDr. C G Knot't ■ 

 Change of electrical resistance of nickel subiected to 

 cross-magnetic _ fields. The nickel was in the form 

 of tape-like strips, which could be rolled into compact 

 coils and set in the air-gap of an electromagnet. 

 Moderate fields were in these circumstances sufficient 

 to produce easily measurable changes of resistance in 

 transverse fields. The nickel coils were made the 

 cores of transformer-wound anchor-ring electro 

 magnets, and by passing a current through the en- 

 velopin!7 wire longitudinal fields of sufficient str-nn-fh 

 ZZt ,f *^'"«^^; , The most curious facts established 

 ve^re these :-(i) Although, as is well known, longi- 

 tudinal mao-netisation is accompanied by increase "of 

 resistance, yet when the nickel is maintained in a 

 steady state of transverse magnetisation the effect of 

 the same longitudinal field superposed upon the trans, 

 yersely magnetised state is in most cases to diminish 

 the resistance. (2) When a transverse field is super- 

 posed upon a steadily maintained longitudinal field 

 the decrease of resistance is numerically greater than 

 when the transverse field acts alone, and this in spite 

 of the fact that a longitudinal field acting alone pro- 

 duces an increase of resistance. 

 Paris. 

 Academy of Sciences, February :).— M. F Guvon in 

 the chair.— L. Lecornu: The security of aeroplanes. 

 I'or the study of the important Question of safety in 

 aeroplanes a society has been formed called the 

 Union pour la sdcurit^ en aeroplane." From its 

 funds It proposes to award a prize of 400,000 francs 

 HI connection with this question. Neither plans 

 memoirs, nor reduced models will be considered; oniy 

 tull-size working machines will be admitted to the 

 competition.— .A. Miintz : Luminosity and plant 

 assimilation. Although in experiments carried out in 

 conhned atmospheres the amount of assimilation has 

 NO. 2259, VOL. 903 



[February 13, igi_ 



been found to depend largely on the intensity of the 

 light to which the plant has been submitted, data are 

 given to show that this is not the case with plants 

 growing in the open air. The probable reason for 

 this IS that the carbon dioxide is present in a much 

 higher proportion in the confined air, and even a 

 dul diffused light IS sufficient to take full advantasre 

 ot the small proportion of carbon dioxide present in 

 outside air.-A. Blondel : The origin of wireless tele- 

 graphy by means of musical sparks. A claim for 

 priority; the author-s first use of this method dates 

 back to 189S.-G. Tzitzeica: Derived networks -D 

 rompeiu : An application of the functional calculus to 

 the theory of functions.— Joseph Peres : The deter 

 mination of all the permutable functions of the first 

 species with a given function.— A. Bilimovitch • The 

 equations of motion of non-holonomial conservative 

 systems.-Paul Jegou : The phenomena occurring in 

 the electrolytic detector not provided with an auxiliary 

 electromotive force and theoretical considerations on 

 the working of electrolytic detectors.— C. Gutto- ■ The 

 duration of the establishment of electrical double 

 retraction. .\ description of experiments showing that 

 m a fie d of force of variable intensity the variations 

 ot the electrical double refraction of bromonaphthalene 

 and carbon bi.uljihide do not follow exactly those of 

 the electric force The results of these ex'periments 

 are in accord with the theory of the orientation of the 

 molecules developed by Langevin.- H. Buisson and 

 L-h. i-abry: A microphotometer designed to measure 

 the opacity of photographic plates.-Jean Meunier ■ 

 Ihe spectra of nebula. In addition to hydro- 

 gen the author identifies some of the 'lines 

 with iron and titanium. The possibility of 

 the existence of iron and titanium in abso- 

 lutely gaseous flames is discussed.— G. Charpy and S 

 Bonnerot : Th- reactions which accompany the osmosis 

 of hydrogen through iron. The passage of hydrogen 

 tliroughiron at 600° C. is shown to result in the 

 elimination of some of the impurities of the metal 

 phosphorus, sulphur, and carbon being removed The 

 conclusion IS drawn from these resultl that iron and 

 steel, manipulated without special precautions in con- 

 tact with air are generally saturated with hydrogen. 

 --J. BougauU and M. Mouchel-la-Fosse : The action of 

 the alkaline sulphites on the cthylenic acids. Certain 

 unsaturated acids instantaneously fix a molecule of 

 sodium bisulphite, and this reaction can be appli-d 

 to the separation of unsaturated and saturated acids 

 I eg. or 2 eg. of benzoic acid has been easily separatee! 

 in this way from i gram of cinnamic acid.— Paul Guerin • 

 Pint,/''"!}",' f^-"ment in the Thymeleacese.-A. 

 Pmard and A. Magnan : The fragility of the male sex. 

 In 52,689 accouchements there were 7056 deaths 

 before or after birth. An analysis of the data, col- 

 ected oyer twenty years, shows that before birth 

 the mortality was the same for both sexes; the in- 

 creased male mortality during and immediately after 

 birth IS attributed by the authors to the mechanical 



infonf^o 1 .f^'''^''''.'''"'^''' '''"^ -^'^'^ of the male 

 infants and not to any inherent delicacy in the male.— 

 J. U de Man : A new observation of Meni-bpe convcxa 

 inhabiting the empty shells of Balanus.-M. Javillier • 

 The substitution of glucinium for magnesium or zinc 

 Z.n,^}T^^ •^.'"''S'""locysth nigra. Experiments 

 a e quoted showing that glucinium cannot replace 

 magnesium or zinc as a catalytic agent in the growth 

 le ," "J°"'.d-Cliarles Lepierre : The replacement of 

 ^nc bv g ucinium ,n the culture of Aspergillus nieer. 

 The results obtained are opposed to those given in 

 the previous papcr.-Louis Duparc : The origin of the 

 nfflnenT '".the alluvial deposits of certahi lateral 

 d Ban.Cre '^'^ }^''^'^-^' N^-'th Urals.-De Montessus 

 de Ballore : Destructive earthquakes and the seasons. 



