August 26, 1897] 



NATURE 



415 



temperature the warm summers are often followed by the 

 mildest winters, during the great periods of relative warmth, 

 and that during the cold periods, the severest winters often 

 occur after cool summers. As it seems probable that the same 

 .rule will hold good in the future, as obtained in the past, it 

 may be expected that the next great period of relative warmth, 

 which should begin about the end of the present century, will 

 fee marked by a series of warm summers, with occasional very 

 jnild winters, in Western Europe. 



We have received the Sitzungberichte der K. Academie d. 

 Wissenschaften <Band. cv. ), containing papers read before the 

 Vienna Academy of Sciences in 1896 Among the numerous 

 papers printed in the various parts into which the volume is 

 ■divided, according to the sections before which they were read, 

 we notice the following : — The secular acceleration of the moon, 

 'by the late Dr. E. v. Haerdtl : a discussion of observations of 

 nvo large meteors seen on January 16 and 25, 1895, and an esti- 

 mation of their paths, by Prof. G. v. Niessl ; the influence of 

 lective absorption on the extinction of light in the atmosphere, 

 y Prof. J. v. Hepperger ; the deflection of kathode rays, by G. 

 Jaumann ; the ultra-violet spark-spectra of metallic elements, by 

 Prof. Franz Exner and E. Haschek. The results now described 

 and illustrated by heliogravure reproductions of photographs 

 Are in continuation of those given in the preceding volume. 

 The lines investigated are comprised between about K — 2200 

 and \ = 4600. Further studies of projectiles, by Dr. Ludwig 

 Mach. This paper is illustrated with several fine reproductions 

 of photographs of moving bullets. On the indispensability 

 •of atomism in science, by Prof. Ludwig Boltzmann ; 

 magnetisation in two dimensions and hysteresis in a 

 rotating field, by Prof. August Grau and Dr. Richard 

 Hiecke ; on the deviation of saturated water-vapour from the 

 Marriott-Gay-Lussac law, by O. Tumlirz ; on the effect of low 

 temperatures (down to 0° C. ) upon the transpiration of plants, 

 by Hans. Molisch ; on the scaling of the reproduced tail in 

 lizards, by Dr. Franz Werner ; geo-morphological observations 

 in Norway, by Dr. Eduard Richter ; morphological and bio- 

 logical investigations of lichens, by H. Zukal ; physical-oceanic 

 investigations in the Red Sea, by Prof, J. Luksch ; remarks 

 upon some problematic fossil structures, by Theodor Fuchs ; 

 new fossil plants in the Radoboj collection of the Liege Univer- 

 sity, by Prof. C. v. Ettingshausen ; geological exploration of 

 North Greece, by V. Hilber ; zoological results of the expedi- 

 tion of the Pa/a to the northern part of the Red Sea, by Dr. F. 

 Steindachner ; on the blood corpuscles of vertebrates, by P. 

 Knoll ; the absorption of bacteria after local infection, by Dr. 

 J. Halban ; on the comparative anatomy of the larynx of mam- 

 mals, by Dr. H. Albrecht ; synthetic investigations of topaz, by 

 A. Reich ; on the occurrence of argon in the gases from a spring 

 at Perchtoldsdorf, near Vienna, by Dr. Max Bamberger. Many 

 other chemical papers (mostly organic) appear in Abtheilung 

 ii.ii of the volume just published. 



The additions to the Zoological Society's Gardens during the 

 past week include a Black-eared Marmoset {Hapale penicillata) 

 from Southeast Brazil, presented by Mr. Samson Clark ; a 

 Laughing Kingfisher {Dacela gigantea) from Australia, presented 

 by Mr. W. L. Chrystie ; a Painted Terrapin ( Clemmys picta) 

 from North America, presented by Mr. C. R. Fisher ; an Al- 

 gerian Tortoise ( Testiido ibera) from North Africa, presented by 

 Captain A. Carpenter, R.N. ; a Black-headed Lemur {Lemur 

 brunnetis, ? ) from Madagascar, two West African Love Birds 

 {Agapornis pullaria) from West Africa, deposited ; a Golden- 

 crowned Conure {Comirus aureus) from South-east Brazil, pur- 

 chased ; a Yak (Piikagus grunnieus, 9 ), a Wapiti Deer (Cervus 

 tauadensis), two Saffron Finches {Sycalis flaveola), two Crested 

 Pigeons (OcypJiaps lopholes), two Triangular Spotted Pigeons 

 ( Columba gumea\ bred in the Gardens. 



NO. 1452, VOL. 56] 



OUR ASTRONOMICAL COLUMN. 



New Southern Variables. — Dr. Gill records the discovery 

 of four new variable stars by Mr. R. T. Innes at the Cape 

 Observatory (Asiron. Nachr., No. 3441). The first three have a 

 variation of about I magnitude, while the range of the fourth is 

 as yet uncertain. Here are the facts :— 



Star. R.A. (18750) Decl. (18750) 



h. m. s. 

 C P. D. -32" -1 376 7 446-4 -3243-6 Mags. 90-97 

 Cord. LC. 8-679h. 8 8 16 -3412-1 „ 6-8-7-8 



Th.-27'^-7724 104522 -27502 „ 8-7-9-9 



Th- 33^-8559 12 34 12 -33 53-1 Certainly 



changed 9 "1-9 5 



The second of the stars in the above list has a period of 

 probably forty-five days. 



Comet 1886 V— Several provisional elements of this comet, 

 which was discovered by Mr. W. R. Brooks, have been 

 calculated, and all have led to the assumption of a parabolic 

 orbit. Mademoiselle Klumpke has, however, undertaken a 

 determination of the definite orbit, using all the available data, 

 and publishes a preliminary result of this computation in the 

 Bulletin Astronotuique for August. She has found that after 

 two trials a parabolic orbit is untenable, but in her third attempt 

 an elliptic orbit with a period of less than looo years was more 

 conformable with the data. The elements finally deduced, but 

 still subject to slight modifications, owing to the discussion of 

 250 observations now in hand, are as follows : — 



T= 1886 June 7, 391319, Paris M.T. 



"■ = 33 54 4977] 

 ft 192 37 27-37 '/-M.Equin. 1886-0. 

 i 87 40 23 67] 

 log^ 9-998572 

 log^/ 9-431056 

 R. 745 years. 



Mademoiselle Klumpke mentions that in her computation she 

 has met with numerous difiiculties in consequence of the great 

 inclination of the orbit, and of the large heliocentric movement, 

 which reached 245°. 



Effect OF Pressure on Series in Spectra.— Prof J. S. 

 Ames and Mr. W. J. Humphreys publish in ^}c^t. Johns Hopkins 

 University Circular (No. 130) a brief account of the results of an 

 investigation to find out the effect of pressure on the lines com- 

 posing series in the spectra of certain elements. To this end 

 photographs were taken of the arc spectra of all the elements 

 which give series at both ordinary and increased pressures. Eye 

 observations were also made. The results were as follows : 

 The lines of any one series of a particular element are shifted 

 alike, that is, according to the same law which is given as 



AA = \j3(/i-A) 

 where \ represents the wave-length, A\ the shit't produced by 

 the increase of pressure/, -/o- and 3 is a constant for any one 

 series of a definite element. The constant & is diff"erent for the 

 different series of the same element, the change being such that, 

 very nearly, 3 for the principal series is one-half 6 for the first 

 sulxjrdinate, and one-quarter that of the second subordinate. 

 Further, the constant fl is different for the same series of diflferent 

 elements, and one apparent regularity which demands attention 

 is that, approximately, the value of J8 for similar elements (that 

 is, zinc, cadmium, mercury) varies as the cube root of the atomic 

 weight. 



In the same journal Mr. Humphreys communicates another 

 note on changes of wave-length due to pressure, which contains 

 some new and interesting observations ; and some of the relations 

 which he has found to hold good, may be briefly referred to 

 here. 



The shift towards the red is directly proportional to the total 

 pressure of the gas. This shift seems nearly or quite independent 

 of temperature (cyanogen bands excepted). The shifts of similar 

 lines of a given element are proportional to the wave-lengths of 

 the lines themselves. Analogous or similar lines of elements 

 belonging to the same half of a Mendelejeff" group shift pro- 

 portionately to the cube roots of their respective weights. The 

 wave-lengths of those substances which, in the solid form, have 

 the greatest coefficients of linear expansion, have the greatest 

 shifts. Finally, the shift of similar Imes is a periodic function 

 of atomic weight, and consequently may be compared with any 



