February i i, 1909] 



NATURE 



431 



have made themselves and the council ridiculous, and 

 would have prejudiced their case as regards the 

 fellowship. 



This issue — namely, the position of women chemists 

 in regard to a society which professes to have no 

 other aims than the promotion of chemistry — is one 

 which is bound to be settled in favour of the women. 

 Men have no prerogatives as regards the study and 

 cultivation of natural knowledge. It is open to 

 women, as human beings, to follow its pursuit if 

 they are so minded, and they have the same moral 

 rights as men to benefit by membership of an 

 organisation which has been created to further its 

 interests. We admit women to our colleges and 

 universities ; they work in our chemical laboratories ; 

 they engage themselves in the business of original 

 chemical inquiry ; we publish their scientific com- 

 munications in our journals; and we confer upon 

 them our degrees in science. Why, then, should 

 the Chemical Society of London be singular in 

 refusing to admit them as fellows? That it is 

 singular is shown by the fact that even a purely 

 professional society — the Institute of Chemistry — 

 admits them. The Society of Chemical Industry 

 places no obstacle in their way, and they are admitted 

 to Continental and American chemical societies. 



The small group of London chemists who have set 

 themselves to oppose the wishes of the main body 

 of the society have thereby raised an issue which is 

 even broader than that which they have sought to 

 evade. It is whether, in an essentially democratic 

 institution like that of the Chemical Society, the 

 will of the majority is to prevail, or whether it is 

 to be thwarted by the machinations of a self- 

 constituted oligarchy which abuses its trust and 

 makes use of its opportunities to gratifv its personal 

 prejudices. Perhaps the general body of the fellows 

 will have something to say on this matter at the 

 forthcoming general meeting of the society. 



PERIOniriTY IN THE SUN AND THE RED 



VARIABLE STARS.' 

 "T^HE mechanisms of the periodicities of the sun and 

 ■•■ stars are matters still of great obscuritv. The 

 cyclic change of the sun's spotted area has long been 

 known, indeed can be traced in the early Chinese 

 observations. In probable association with this are 

 periodicities of facular and floccular areas, and of 

 prominence activity. Coronal forms have been shown 

 to change in type from point to point of this solar 

 cycle, while recent observations of the so-called " solar 

 constant " have shown its intrinsic variability. This 

 last also is likely to be periodic. Such intimate first- 

 hand knowledge is impossible in the case of the stars. 

 Their integrated light changes alone can be examined. 

 For variable stars about or below the solar level, 

 according to the classifications of Secchi, Lockyer, or 

 Pickering, some idea of the details of their variation 

 m,-iy be obtained by analogy with the sun. In deal- 

 ing with the red variable stars this method has been 

 followed in the publication under review. This is an 

 " Essai d'une Explication du M^canisme de la P(^rio- 

 dicit(5 dans le Soleil et les Etoiles rouges variables," 

 by A. Brester, Jz, Docteur es Sciences, published bv 

 the Academy of Science, Amsterdam, iqo8. The first 

 accounts of the theory have been already reviewed in 

 Nature (vol. xxxix., p. 402, and vol. xlvii., pp. 433, 

 434). Its main features remain unchanged. The pre- 

 sent statement gives it in the light of more recent 

 know^ledge, amends it in detail, and extends its appli- 



1 "Essai d'une Explication du Mi?.:anisme de la Periodicity dans le 

 Soleil et les Eloiles rouges variables." By A. Brester, J?. Eerste Sectie. 

 Deel IX., No. 6. Pp. 137. (Amsterdam: J. Muller, 1908.J 



NO. 2050, VOL. 7g] 



cation, more especially, to the case of red variable 

 stars. 



A short preliminary re-statement of the theory is 

 perhaps desirable. In the case of the sun there is pos- 

 tulated a hot fluid globe made up of concentric layers 

 of different substances arranged, more or less, accord- 

 ing to their densities, and having angular velocities 

 increasing with the depth in the sun. For the stability 

 of such a stratification a relatively tranquil sun is 

 demanded; such disturbances as are admitted are 

 considered as being of the order of feebleness of ter- 

 restrial winds. 



Radiation from the outermost solar layers pro- 

 vokes condensation, retarded by exothermic chemical 

 action, which, falling as a torrential rain, forms the 

 photospheric clouds. If the loss of heat above exceeds 

 the gain of heat below the clouds increase in thickness 

 and gradually reach lower and lower levels. In their 

 descent they leave behind the finer condensed material, 

 which serves to explain the loss of solar light at the 

 limbs and the "yellow veil." The extreme brilliance 

 of the photospheric clouds is likened to that of an in- 

 candescent mantle, the brightness of which seems to be 

 associated with some subtle chemical activity. The 

 breaks in the photosphere through which the re- 

 vaporised clouds ascend constitute the spots, the 

 vapours of which, though at least equal in temperature 

 to the photospheric clouds, have smaller emissive 

 powers. An upthrusting of faculas would usually pre- 

 cede a spot, which seems to correspond to the latest 

 observations, while the facular lag and equatorial 

 acceleration of spots would follow from the assumed 

 distribution of angular velocity. 



The periodicity of the thickening and sinking' of this 

 photospheric cloud and its re-conversion into uprising 

 vapour, which again condenses at a high level, grows 

 in thickness and slowly reaches lower levels once more, 

 is obviously too indefinite for mathem.atical treatment, 

 so that the eleven-\'ear cycle and the minor periodicities 

 are still only facts of observation. An intensification 

 of this clouding up of radiation and an increased 

 periodic spottiness represent the extension of the theory 

 to the red variable stars. 



The tranquility and absence of eruptive phenomena, 

 which the author regards as essentia to his theory, arc 

 fearlessly imposed. .Since the delicately poised strata 

 must not be disturbed, the directly observed veloci- 

 ties, both on the photosphere, as spot and floccular 

 changes, and at the limb, as prominence activities, are 

 discredited as movements of matter. A transference 

 of luminescence serves to explain them. The displace- 

 ments of some solar lines indicate, on the principle of 

 Doppler, velocities in the line of , sight which the 

 author holds as " impossible and absurd." Since line 

 displacements are now known to be produced by other 

 agencies, as well as by line-of-sight velocities, 

 Doppler's principle is held to be untrustworthy. The 

 invariability of the general Fraunhoferic spectrum is 

 adduced as evidence of this photospheric calm, while 

 the outermost different angular velocities of some of 

 the solar layers, as indicated in the recent work of 

 Prof. Hale, show, according to the author, that the 

 " supposed solar eruptions cannot exist." 



The above is a very brief sketch of the theory which 

 in the essay is treated in great detail. A wealth <!f 

 pertinent quotations and references is brought to its 

 support, the collection of which must indeed have been 

 a labour of love. 



The parts which exothermic and endothermic 

 chemical actions play in the theory are interesting. 

 Dissociation, a distinctive solar theory of Sir Norman 

 Lockyer, is used in this connection, though the rela- 

 tive temperature and the direction of motion in the 

 umbrae of spots are the opposite of those given in 



