128 



NATURE 



[July 27, 1911 



1 Velocity of tub Son, and Doppli 

 iple. — In No. s, vol. xxxiii., of The 



Mr. A. Cotton has a paper dealing with the 



oi applying Doppler's principle, purely and 



determine the radial velocitj oi the sun's parts 



from the measured displacements oi the lines in the olai 



pectrum. He shows that the Fad thai the sun is 



surrounded by an extensive, turbulent atmosphere, in 



ind thermic qualities oi vastly different 



magnitudes coexist, is sufficient to call for prudence when 



applying a simple, single interpretation to the displace 



Peculiar Stellar Spectra and Selective Absorption 

 in Interstellar Space. — We have just received No. 51 of 

 the Lowell Observatory Bulletins, in which Dr. Slipher 

 idi nee for the existence of some material in 

 interstellar space which differentially absorbs star radia- 

 tions. 



\ spectrum of /3 Scorpii displayed a sharp K line, 



as all the other lines in this " Orion "-type spectrum 



diffuse and broad; and while the latter show a 



Doppler displacement equivalent to a range of 240 km., 



the K line gives no sign of shift. 



Further research indicated that <r, S, and it Scorpii 

 exhibit the same phenomena, and in this are like 8 Orionis, 

 £ Ophiuchi, 1 and ?j Orionis, o Persei, and other binaries. 

 Apparently the matter wherein this calcium absorption 

 takes place is, in each case, independent of the star, and 

 the theory at one If that it takes place in 



an absorbing medium lying between us and the stars. 

 Evidence for this accumulates in other directions ; and the 

 matter is one of fundamental importance to which the 

 tion of astrophysicists must soon be directed. Dr. 

 Slipher asks for cooperation ; as a preliminary, the 

 examination of all the spectra of " Orion "-type stars in 

 existence would indicate those in which the independent 

 behaviour of the calcium, and maybe the sodium, lini s 

 was marked. 



French Astronomical Works. — Readers of French will 

 find that " Quelques Heures dans le Ciel," a franc "paper 

 by the Abbe Th. Moreux, gives a very complete, 

 lucid, and well-illustrated resumi of present-day astro- 

 nomy. The chatty freedom with which the various points 

 are explained will attract the beginner, and the illustra- 

 tions will considerably assist his comprehension. 



Those who wish to practise astronomy will find the 



Commandant Ch. Henrionnet's " Peth traits d'Astronomie 



lie " a useful summary and guide. The author 



describes the books and the instruments used, the simpler 



d employed, and gives a brief statement of the 



ling things in various constellations. Gauthier- 



Villars publish the book at 1.75 francs. 



THE MAN CHESTER MEETING OF THE IN- 

 TERNATIONAL [SSOCIATION OF SEIS- 

 MOLOGY. 



""THE meeting of this association, which was held in 

 Manchester on July iS_ 2 2, proved to be one of 

 considerable interest and importance. The time spent on 

 busine and dn was less than at prei 



ings, 50 that more was left for original communica- 



On the opening day, the Vice-Chancellor of the Uni- 

 lestei i eceived the delegates in the 

 Whitworih Hall, and during the da] a telegram was 

 ived from the the Board of Education in 



: — 

 "His Majesty's G01 hi irtily welcome youi 



i.ition, and wish success to their deliberations. 

 They rejoice to see thi attempt to 

 internationally, which was initiated by the British V oci 

 tion under the influence of Dr. Milne, bearing fruit, 

 through your proceedings on British soil." 



Amongst r itions received, probably the most 



1 description bi Prince Galitzin of his 



instrument for measuring fl component of 



motion of the soil. The instrument shown at the 



has been acquired F01 the observatory at Eskdale- 



e it will 1"' set up as soon .1 • pri pel Founda- 



1 built. 



NO. 2178, VOL. 87] 



Mr. Oddone shov d an ingenious and simple appar; 

 for measuring the elasticity of rocks. an d Mr. Wiei 

 communication on the constitution of the interior ol 

 earth gave rise to an interesting discussion. 



An instrument w: hown at the meeting con- 



structed by the Cambridge Scientific Instrument Company, 

 with which it is intended to count the numb 

 which strike the shore in a given time in order to 

 whethet the period of these "waves is - the 



of tli" microseismic disturbances. This instrument 

 has already been taking records on the coast of Northum- 

 berland, under the superintendence of Mr. Morri 



There was a reception in the Town Mall on one of the 

 days of meeting, which was well attended, and a dil 

 n by the university on the last evening. 



Saturday, July 22, was given up to 1 ,) at 



the invitation of the director of the Meteorological I 

 and of Mr. and Mis. J. Walker, nearly twenty fot 

 delegates visited the new magnetic and meteoroloj 

 tory at Eskdalemuir. 



The foreign delegates both privately and publicly ex- 

 pressed tl..ii gi nil;.. 1 le,, at the presence of Dr. Milne, 

 and, in addition, British men of science were well 

 represented, amongst others by Sir George Darwin, Profs. 

 Lamb, Love. Knott, Mr. Oldham, and Dr. Shaw. 



Prince Galitzin was elected president, and Mr. Lecointe 

 vice-president, for tl I 1 years, dating 



from April, 1912. 



The opening address delivered by Trof. Schuster en 

 July 18 is subjoined. 



Some Problems of Seismology. 



Since "in important changes have ti 



place in our i entral Bureau. Increasing age has 

 compelled Prof. Gerland, to whose strenuous efforts the 

 foundation of this association is mainly due, to resign the 

 directorship of the seismological station at Stras ; 

 Prof. O. Hecker, who has been appointed in his place, 

 thereby become the director of the Central Bureau, and 

 you will agree with me that no better choice could have 

 been made. The excellence of his work is well known to 

 you, and since he has entered into his new office 1 

 with characteristic energy already done much to make 

 the bureau more efficient for its international work. You 

 will have an opportunity of showing your confide, 

 him when we decide on the locality of the Central Bureau 

 for the next period of four years, as (hough we hai 

 official voice in the choice of the director, it lies in our 

 power to move the seat of the Central Bureau at any 

 meeting of the general assembly if such a course 

 desirable in the interests of our work. 



Our association primarily deals with the study ol 

 causes of earthquakes and of their effects, but the h 

 which the public shows in our investigations is mainl; 

 to the sympathy roused by the human suffering which 

 follows the trail of eismic 1 raphes. \t present 



we feel helpless, though perhaps not altogether hopeless, in 

 the face of the destructive convulsions of the earth. The 

 problem of constructing buildings which can withstand 

 shocks of earthquake does net enter into our programme- 

 but it has been asked, and the question will lie 

 during the present meeting, whethei tl 

 liminarv indications which would allow us 1 

 occurrence of a dislocation of the soil and take precautions 

 to mitigate to some extent its power of destruction. 

 Remembering how meteorologist I eeded in pre- 



venting loss of lil i predicting the cot 



cyclones in the Indian Ocean or the Gulf ol U 

 might be tempted to hope that similar warnings mai 

 11. in fight On' dangers of an earthquake. I am afraid 

 that the ia ;es net quite anal I 1 vi n if our 



knowledge should allow us in the future to Form p 

 tions of equal certainty, tl"' dai tpanying such 



predictions may overbalance its benefits. The precautions 

 which can be takl n in a harbour against an approaching 

 storm are of a comparatively simpli character, and the 

 meteorologist is therefore jusiified in warning us against 

 a probable si,,,,,, which does not appear; but would the 

 seismologist be justified in creating a panic and dislocating 

 trade by predicting an earthquake which failed to take 

 placi ! We can easily forgive the meteorologist who fore- 



