June, 1908. 



KNOWLEDGE. 



133 



the process went ou to infinity could never exceed a very 

 limited amount. It is, however, essential to this theory 

 (assuming that no light is lost in transmission) that the 

 thinning-out should go on to infinity. If it came to a 

 stop anywhere we should arrive ata different result ; and 

 a thinning-out extending to infinity suggests that we are 

 near the centre of the system. 



I may add, however, that tlie constant detection of 

 additional stars \>y more powerful instruments does not 

 disprove the finiteuess (in space) of the visible universe. We 

 may be discovering fainter stars within the same space-limits 

 as those already detected. There are still undiscovered 

 stars (asteroids) within the limits of the solar system, and 

 perhaps our nearest self-luminous neigiibour has yet to be 

 detected. Till lately we did not dream of the vicinity of 

 Eros. On this subject (and many others) we must, I 

 think, be content to wait and watch. 



W. H. S. MoNCK. 



[The point is not new. It was put forward very clearly 

 l)y Mr. Charles E. Inglis in Knowledge, 1900, March, 

 p. 6-5. It will be remai'ked that it assumes the proposition 

 Dr. Wallace seeks to establish of the essentially central 

 position of the solar system. — E. Walter Maunder.] 



THE BIBLICAL • MAZZAEOTH." 



TO THE EDITORS OP KNOWLEDGE. 



Sirs, — Can any of your readers tell me what star or 

 constellation the word " Mazzanith " means in the 38th 

 chapter of Job and 32ud verse ? 



James B. Bowek. 



Claremont. Teignmouth, Devon. 

 •24th March, 1903. 



[There is an evident pai-allelism between Job ix. 9 and 

 Ji>b XXXVIII. 32; and the " Mazzaroth " of the latter 

 answers to " the chambers of the south " of tlie former. 

 These are without doubt the twelve signs of the zodiac 

 through which the sun passes in the course of the year. 

 Each is brought out in its own '' season," whilst the 

 circumpolar constellation of the "Bear" {see the 

 Revised Version) is always above the horizon, but is 

 "guided" with her train in her unceasing circuit round 

 the pole. — E. Walter Maunder.] 



Astronomical. — The interesting ])roblem presented by 

 the feeble nebulosity surrounding Nova Persei has been 

 attacked in a most courageous manner by Mr. Perrine, of 

 the Lick Observatory (Circular. No. 33). On account of 

 its exceeding faintness. any attempt to determine the 

 spectrum of this nebulosity seemed almost hopelc?ss, but 

 in view of the great importance of such knowledge, a 

 photograjihic spectroscope of small dispersion was specially 

 constructed for the purpose in connection willi the 

 (U'ossley reflector. Commencing with 7h. 40m. on the 

 night of October 31st, 1902. and ending with 9h. 2.'>m. on 

 November 4th, a photographic plate was exposed to the 

 spectrun) of "condensation D," for no less than 34h. 9ra., 

 and it must have been very gratifying to find that the 

 resulting negative showed even a very faint spectrum. A 

 careful discussion of this photograph has led to the con- 

 clusion that the spectrum of the nebulosity in Novemlier. 

 1902, was not the spectrum of an ordinary gaseous nebula ; 

 that it was not the spectrum of the Nova since the latter 

 became nebular: and that it more nearly resemblfd the 

 spectrum of the Nova during the tirst lew davs of its 



outburst. This spectroscopic evidence is considered to be 

 not inconsistent with the theory that the luminosity of the 

 nebula is due to reflection of the light emitted by the 

 Nova at the time of its greatest brightness, but it is not 

 regarded as in itself quite sufficient to establish this 

 theory. 



Great activity <m the part of the staff of the Lick Ob- 

 servatory is indicated by other circulars recently puldished. 

 No. 29 gives particulars of measures of 117 new double 

 stars, more than half of which have distances not 

 exceeding one second. No. 30 gives observations, elements, 

 and ephemeris of Comet a 1903 (Giacobini). No. 31 

 announces the variable velocity in the line of sight of 

 V Andromedse, ir* Orionis, a- Gemmorum, and i Argus ; 

 it is also noted that 4>- Orionis has the great radial 

 velocity of nearly 100 kilometres per second. 



It has long been understood that spectroscopic deter- 

 minations of the velocities of the components of a binary 

 star, taken in conjunction with ordinary telescopic deter- 

 minations of the orbit, would lead to a very exact 

 knowledge of the parallax of such a system. This method 

 of arriving at the parallax of a star has recently been 

 successfully applied at the Lick Observatory to Delta 

 Equulei (Circular 32), in which case the period is only 

 .5-7 years, and the motion therefore relatively rapid. At 

 the last periastron passage, aijout the middle of 1902, the 

 relative velocity of the two components in the line of sight 

 was found to be 20'.5 miles per second, and the resulting 

 value of the parallax is 0"071. From this it results that 

 the total mass is 189 times the sun's mass, and as tlie 

 magnitudes are slightly unequal, the mass of the lirighter 

 star probably does not differ much from that of the sun. 

 At periastron the distance of the components is about two 

 astronomical units, and at apastrou five of these units, 

 the orbit being verv eccentric. It is interesting to' note 

 further that, broadly speaking, the spectra of the stars 

 are of the solar type. 



It is intei'esting to learn that Nova Geminorum would 

 not have escaped record even if it had not been discovered 

 l)y Prof. Turner during its brighter stages. The nearly 

 continuous photographs of the heavens made at the 

 Harvard College Observatory indicate that while there 

 was no star as bright as 9th magnitude in the positicm of 

 the Nova on March 3rd, the Nova was about mag. 5 on 

 March 0th, after which the brightness diminished. On a 

 photograph taken on March 2i)th. the spectrum of the star 

 is very conspicuous, showing several blight lines, which 

 at once distinguish it from ordinary stars. By the end of 

 March, transition to the nebular s[>ectrum iiad already 

 commenced. — A. V. 



Botanical. — The remarkable Darlilia which, until 

 recently, has been known in Europe only from dried 

 sjiecimens, .seems likely in the future to become a familiar 

 plant in this couutr}'. It is a native of Central China, 

 whither a collector was sent a few years ago by Messrs. 

 Veitch, of London, for the special |)urpose of procuring its 

 seeds. He has succeeded in this, and has brought home 

 some additional inforuKitiou as to the peculiarities and 

 distribution of tlie tree. The Davldia is a mom>typic 

 and somewhat anomalous genus of Cornace<T.\ It reaches 

 a height of thirty feet, and is not unlike our common lime 

 tree in foliage. Its flowers are unattractive, but a striking 

 effect is produced by the presence of a i>air of very large 

 white bracts just below every flower or flower-head. The 

 mode of germination of the seeds is noteworthy. The 

 fruits are ellipsoid, about an inch and a quarter long, 

 the outer layer pulpy and the endocarp bony and grooved. 

 It is indeliiscent, but after Iving several months in the 



