134 



NATURE 



[December 12, 1901 



of the phenomena connected with new stars. It would 

 seem, however, that such f;reat velocities pointed rather 

 to a violent collision of some sort than to an outburst 

 within a dark and comparatively cool body ; but whether 

 a collision of a solid body with another, or the passage 

 of a solid body through a gaseous nebula or a swarm of 

 meteorites is uncertain." 



It appears to me that the full significance of the recent 

 observations has not been grasped by those who have 

 commented upon them. It seems difficult to imagine 

 that most of the new stars, like the bright-line stars and 

 bright-line nebula-, are not at the distance of the Milky 

 Way as well as in its plane. If this be so, then this dis- 

 tance is enormous. Let us assume — the assumption is a 

 moderate one — that it is represented by a parallax of half 

 a second, and see how it works out on the two-minute 

 sc]uares marked in the diagrams. 



.■\t the No\a situated at such a distance, i minute of 

 arc represents about 120 times the sun's distance from 

 the earth. 



The apparent movement of the condensations is stated 

 to have been \\ minutes in 48 days, say, approximately, 

 I minute in a month, say, again, four times the distance 

 of the sun in a day. 



I do not say that such rapid translations of masses of 

 matter are impossible, certainly there are no precedents 

 for them ; but my point is that there is absolutely no 

 necessity for the assumption of such movements, and 

 that the apparent change of position of these con- 

 densations can be explained otherwise than by move- 

 ment. Indeed, such an explanation is not hard to seek 

 when the meteoritic theory of new stars is closely con- 

 sidered in all its aspects. It is a well-known fact 

 that the majority of new stars that have been recorded in 

 more modern times, when the spectroscope has been 

 available for their study, have ended by becoming 

 nebuht. The meteoritic theory explains the appearance 

 of a new star by the interpenetration of two or more 

 swarms of meteorites, a nebula being the representa- 

 tive of an ordinary great swarm, a comet near the 

 sun being a representative of a small one disturbed by 

 tidal action. The appearance of a new star is produced 

 by the luminosity depending upon the celestial clashing. 

 It is not difficult to conceive a system of several swarms 

 of meteorites all performing their individual orbits, and 

 so long as no two systems collide, the whole system will 

 be invisible ; but should a collision occur they will at 

 once become visible, and the more violent the collision 

 the brighter will be the light and the greater will be the 

 luminosity of the "new star" which makes its appear- 

 ance to chronicle the event. 



Now suppose a nebula invaded, not by one, but by 

 many swarms, under such conditions that the colli- 

 sion effects vary very greatly in intensity. In the pre- 

 sent case the most violent one we began to know about 

 some months ago ; it constitutes Nova Persei. The least 

 violent ones occurring in other parts of the disturbed 

 nebula, almost immeasurably removed, i.e. more than 700 

 solar distances away, we only learn of from the recent 

 photographs The disturbances they chronicle are so 

 feeble that to see the effect of them 7 hours' exposure 

 with a 3-foot reflector are necessary, hence they soon die 

 out ; while they are dying other disturbances in other 

 parts of the nebula arise. There is probably, therefore, 

 no question of motion from place to place, we are 

 dealing simply with different disturbances occurring in 

 different places. 



It is impossible to think that the great nebula which 

 has now been photographed while the new star is still in 

 being did not exist there a few months ago ; and it is 

 important, further, to remark that the nebulous matter 

 already photographed in the region round the Nova is 

 very probably only a portion of the actual amount of 



NO. 1676, VOL. 65] 



matter existing there, and that if the disturbances 

 coritinue, more of the remaining portion may become 

 visible. This, in fact, seems already to have been 

 established, for Ritchey found later that the nebula 

 "seems expanding in all directions." At the same 

 time it may be stated that Campbell notes that the 

 condensation n has remained unchanged, while there 

 has been a further "movement" in the case of a 

 and n, the "movement" of c being doubtful. There 

 seems little doubt that later photographs will throw light 

 on this question, but a matter to be regretted in this con- 

 nection is that no photographs are available for the period 

 during which the well-marked variability of the Nova was 

 observed. These occasional outbursts of light were, we 

 can now imagine, due to other disturbances of the nebula 

 intermediate in intensity between that which caused the 

 Nova itself and the other exceedingly faint ones now 

 being photographed. 



One important conclusion can, at any rate, be deduced 

 from the Lick photographs, and that is that such explan- 

 ations as explosions on solid globes, worlds on fire, vol- 

 canic eruptions, &c., must be considered less probable now 

 that a great nebula is shown to be associated with many 

 disturbances of \ery varying intensities. Formerly we 

 had to wait for the death of a new star before the appear- 

 ance indicating the existence of a nebula was manifested, 

 and hence arose the idea that a star changed into a 

 nebula, thus reversing the ordinary process of evolution. 



NORM.AN LOCKYER. 



NOTES. 



The four Nobel prizes were distributed at Stockholm on Tues- 

 day evening before a distinguished audience, among whom were 

 the Crown Prince and other members of the Royal family o 

 Sweden. Each prize was of the value of 200,000 francs. The 

 prize for medicine was awarded to Dr. E. A. Behring, the prize 

 for 'chemistry to Prof. J- H. van 't Hoft", the prize for physics 

 to Prof. \V. K. Rontgen, and the prize for literature to M. Sully 

 Prudhomme. 



It is officially announced that the Board of Admiralty have 

 received with much regret the resignation by Sir William H. 

 White, K.C.B., F.R.S., in consequence of ill-health, of the 

 appointment of Director of Naval Construction, which he has 

 filled since 1885 with great distinction. They have appointed 

 as his successor Mr. Philip Watts, F. R.S., who has held during 

 the same time the post of director of the war shipbuilding 

 department of Messrs. Sir William Armstrong, Whilworth 

 and Co., Ltd., and naval architect to the company. Mr. 

 W.-itts has done much original scientific and experimental work 

 in connection with investigations of the stability of ships and 

 floating bodies, the oscillations of ships in still water and 

 amongst waves, and the propulsion and manceuvring powers of 

 ships. 



The Berlin correspondent of the Times states that the esti- 

 mates for the German Army include a vote for the new military 

 technical college which the Government will open in the course 

 of next year. The necessity for some such institution has been 

 impressed upon the military authorities by the advancing 

 scientific requirements of modern warfare, which are now too 

 numerous and too varied to be provided for adequately by the 

 resources at the command of the existing Staff College. There 

 are branches of technical knowledge which, although they can- 

 not strictly be classed as military, are nevertheless indispensable 

 for the soldier. Among such subjects are steam-power, elec- 

 tricity, mechanics, tlie construction of boats and bridges, and 

 the establishment of means of communication. In recognition 



