u 



KNOWLEDGE & SCIENTIFIC NEWS. 



rjANUARY, 1907. 



western mountain ranges in North and South America. 

 From a China Weather Service Circular issued from the 

 Zi-Ka-Wei Observatory, near Shanj;;hai, we learn that ihe 

 Valparaiso earthquake was rej^islered quite distinctly. Ihe 

 first movements or prelimin.iry liemors of the instrument 

 began on the Friday morning at Xh. ii)m. 24s. a.m., China 

 Coast lime. .\s N'alparaiso, at the mouth of .Santiago 

 Chile river, is nearly at the .\ntipodes of Shanghai, the 

 distance in a straight line across the earth is about 1^,715 

 kilometres, (jiving to the vibrations an estimated velocity 

 of ten kilometres per second, the e.uthquake must have 

 begun 2ini. 12s. sooner at the place of the disaster, viz., at 

 "h. 58ni. 12s. a.m. on the 17th, China Coast time, or at 

 6h. s8m. p.m. on Thursday i6th, i.e., i,^ hours sooner, by 

 the time of the 7 hours zone west of (ireenwieh. There 

 may be some dilTerence in this estimate if the zone time is 

 not employed in Chile. As an indication of the severity of 

 the shock it may be noted that the w.ives registered at 

 Zi-Ka-V\'ei, almost at the other end of the earth's diameter, 

 exceeded 2.7 mm. in amplitude. The end of the disturbance 

 took jil.ice .-It iih. Kjm. a.m. 



Chromospheric and Sunspot Spectra. 



Observing with the l;irgc spiel niscopr and telescope ;il 

 Princeton, "U.S.A., \V. .M. .Milchell has been able to obt;iin 

 a new series of determinations of the lines characteristic of 

 sunspots and of the chromo-.phere. Comparing these with 

 his first series, it was found that the selections of widt-m-d 

 lines of the spot spectra during the two periods were so 

 similar that it was unnecessary to publish a new list. In 

 the cases of reversed and weakened lines, however, this 

 constancy does not hold, many new lines of both classes 

 being detected, and a list of these is given, as well as a 

 table of the lines seen bright in the spectrum of the sun's 

 limb, between the wave-lengths 4876.59 and 688^.33, 

 showing their origins and intensities. Considering these 

 facts in relation to phenomena which have been observed 

 in experimental laboratory research, it is pointed out that 

 the presence of hydrogen in the chromosphere may cause 

 certain lines to be suppressed to such an extent that they 

 become invisible against the background of the sky. This 

 is in agreement with the observations of Fowler, that the 

 high-level chromospheric lines are enhanced lines, since it is 

 probable that the proportion of hydrogen is greatest high up 

 in the chromospheric stratum. Lower down in the re- 

 versing layer other lines gradually make their appearance. 

 In these high-level gases the emission co-efficient would be 

 greater than that of the lines caused by gases at the lower 

 levels; therefore, the absorption of the lines would be less, 

 and, in consequence, across the dark umbra of the sunspot 

 such lines would have an enfeebled or weakened intensity. — 

 (Astrophysical Jmirnal 24, pp. 78-94, September, 1906.) 



Brilliancy of Mira Ceti. 



The well-known variable star Ceti, or Mira, as 

 it is usually called, is now a very prominent object in the 

 scuth-eastern sky at sunset. Attention has been drawn to its 

 appearance this maximum in that it has attained to con- 

 siderably greater brightness than is usual. It is to be 

 hoped that all w-ho have spectroscopic means of observation 

 will obtain records as often as possible. The spectrum of 

 the star is very interesting, and to some extent peculiar; it 

 resembles a Orionis (Betelgeuse) with respect to the dark 

 lines and bands or flutings, but, in addition, there are 

 bright hydrogen lines, which appear to fade out as the star 

 becomes fainter. There is no direct resemblance to the 

 spectra of new stars, so that in this case the eclipse theory 

 is supposed to be a likely explanation of the phenomenon, 

 but the chief difflculty in the way of accepting this is that 

 the lines, both bright and dark, do not show any ap- 

 preciable evidence of motion. 



Peculiar Phenomena of Sunspot 

 Penumbrae. 



M. S. Chevalier, writing from the Zo-.Sai Observatory in 

 China, calls attention to a peculiar appearance sometimes 

 noticed on the inner edge of the penumbras of sunspots. 

 This takes the form of a ring of increased brightness im- 

 mediately surrounding the umbra. It is evident that the 

 phenomenon is not characteristic of all spots, as it has often 

 not been seen when specially looked for. In the paper the 

 author gives a series of photographs of spots showing the 



bright ring at various stages. In the case of a spot show- 

 ing this feature it does not appear to vary as the spot 

 crosses the disc, but observations show th.it the first ap- 

 pearance of it comes out on the north and south of the 

 nucleus, while the spot is entering on the visible hemisphere, 

 then on the east, and finally on the west side. When the 

 spot is approaching the w<'st limb the tlisappe.-ir.irue begins 

 with the east side, then the west, :md fin.'dlv the north and 

 south. It is probable th.it sunspots h.'iving a regul.ir out- 

 line present the phinomenon with the more marked 

 biilliaiuy. ( .l.s7i()/'/i i/.s/ni/ ./(.i/c/ii// 24, Ncivcmlicr, igo6.) 



Calorific Emission of the Sun. 



MM. Fery .-md Milloch.iu, coiUiiuiing tlu'ir observations 

 with the eyepiece thermopile, give further v.-ilues of the 

 prob.ible absolute temperature of Ihe sol.ar disc. These are 

 5,888" and 5,963", with a possible error of ± 15". Experiments 

 were also undertaken to determine the variation of emission 

 of .several substances at high temperatures, including nickel 

 oxide, magnesia, and platinum. — (Comptes liendus 143, 

 November 12, 1906.) 



BOTANICAL. 



By G. MASsicii. 



Origrin of Elementary Species. 



I'koi-kssor Hugo de ViJiiis, whose name is well known in 

 connection with what has been termed " nuitation," or the 

 sudden appearance of elementary species in the vegetable 

 kingdom, has recently (rreic. Amer. Vhil. Hoc.) expressed his 

 views in general terms. Darwin's principal conception as 

 to the origin of species was that their gradual evolution de- 

 pended on the same laws as those that underlie the evolu- 

 tion of races and varieties under culture. This implied time, 

 coupled with much uncertainty, and did not afford the 

 necessary evidence for founding a satisfactory theory. Until 

 quite recently the method adopted for producing new strains 

 was by the slow process of gradual elimination, until the 

 desired strain was obtained in a pure and permanent form. 

 De \'ries, on the other hand, maintains that species are not 

 changed into one another, but are permanent, giving ofT 

 from time to time, sideways as it were, aberrant individuals. 

 Such individuals constitute his mutants or new species, and 

 experiments have proved that, in the main, their characters 

 are constant and hereditary from their first appearance. This 

 is, briefly, De Vries' unit-characters idea, which is the basis 

 of his theory of the origin of species by mutation, which, in 

 turn, leads to the acceptation of saltatory changes, com- 

 monly known as sports, as the most probable way em- 

 ployed by Nature to produce new forms. Most of our 

 ordinary agricultural crops are composed of elementary 

 species, and, again, each cultural variety contains numerous 

 sharply-defined types. These types are distinct in botanical 

 characters, and in those properties which decided for or 

 against their utility. By careful searching, the proper type 

 for each special requirement may be perpetuated. The 

 modern method of perpetuating a desirable strain, say, of 

 a cereal, is as follows : — In each thousand plants there are 

 a few phenomenal yielders, and the method of single-seed 

 planting makes it possible to secure these plants, from 

 which new varieties can be made. If these selected plants 

 had been only extreme varietal fluctuations, they would 

 have shown variability and retrogression to mediocrity. As 

 this did not prove to be the case in the experiment quoted, 

 De Vries considers that these phenomenal yielders were, in 

 reality, elementary species, which had remained hidden until 

 rescued by the process of single-seed planting, or, in other 

 words, commencing from the seed of a single individual. 



The older, and what may be termed the rule-of-thumb, 

 process for obtaining an improved strain consisted in select- 

 ing a number of ears of exceptional size, or possessing in 

 some degree the qualities desired. These were mixed to- 

 gether and sown, and it was only by a long process of 

 elimination, year by year, that the desired result was ob- 

 tained. The explanation of this is that in all probabilitv 

 several elementary species were included in the first selection 

 of ears, hence the necessarily long period required for 

 eliminating all except the very best elementarv species, 

 which, when once obtained, remains permanent. The 



