March 23, 191 1] 



NATURE 



125 



T 



VELOCITY OF EARTH MOVEMENTS. CAUSED 

 BY THE MESSINA EARTHQUAKE. 

 O the Reale Accademia delle Scienze di Torino (1909- 

 10, p. 355) Prof. G. B. Rizzo has contributed an 

 interesting paper on the velocity with which earth move- 

 ments occasioned by the earthquake which ruined Alessina 

 on December 28, 1908, were propagated to different parts 

 of the world. First he gives in detail the observations 

 made with various types of seismographs at no stations. 

 These he sums up in tables, which show for the pre- 

 liminary tremors or Pj, their followers or P^, and the 

 large waves or P3, the time taken by them to travel from 

 their origin to these various stations, their average super- 

 ficial velocity, and the velocities with which the two first 

 types of movement may have passed along paths corre- 

 sponding to chords. The first results are also shown as 

 curves drawn on squared paper, the two ordinates, re- 

 spectively, referring to time and distance. The greatest 

 distance considered is 10,000 kilometres, or 90 degrees, 

 although the tables give results to distances exceeding 

 18,000 kilometres, or 163 degrees. Dr. Rizzo remarks 

 that none of these curves show the flexure near the 

 epicentrum which Schmidt, like Seebach, has used to 

 determine the depth of the hypocentre. The absence of 

 this is taken by Dr. Rizzo to indicate that the origin of 

 the Messina earthquake was very shallow, a conclusion 

 which I do not think will be shared by all seismologists. 

 Many seismologists will, however, agree with him when 

 he bases the idea of a shallow origin upon the compara- 

 tively small area of destructivity. 



Up to a distance of 1500 kilometres from the epicentre 

 the velocity of all three phases of movements is constant. 

 The inference from this is that up to such a distance the 

 movements are propagated within the crust of the earth, 

 which is estimated as having a thickness of 44 kilometres. 

 From this distance there is a marked increase in the 

 velocity of the first phase, which, however, is not shown 

 by the succeeding phases. The third or large-wave phase 

 he divides into three parts, which he calls L^, Lj, and L,. 

 Lj appears to correspond with the commencement of 

 maximum motion, whilst L^ is the maximum movement 

 itself. Lj is the phase which travels the slowest, but if 

 this is to be accepted as a definite and a recognisable 

 phase in a seismogram, there seems to be no reason why 

 we should not also accept very many other phases, which 

 might be indicated by the letters L,, L,, L^, &c. 



Of late years, very many hodographs of the character 

 of the one now presented to us by Prof. Rizzo have been 

 constructed. Prof. H. F. Reid has given us an excel- 

 lent set of time curves relating to the San Francisco earth- 

 quake of 1906. Up to a distance of about 55 degrees 

 from the origin these indicate velocities somewhat higher 

 than those given by Prof. Rizzo, but beyond that distance 

 they are very similar. This kind of difference which we 

 find in the work by different seismologists may be due 

 to differences in the manner in which they have inter- 

 pretated seismograms, but it is much more likely to arise 

 from the non-recognition of all the elements which should 

 be considered when carrying out these particular investi- 

 gations. J. Milne. 



THE EBRO OBSERVATORY OF COSMICAL 



PHYSICS. 

 ■pL OBSERVATORIO DEL EBRO is situated in 

 ■^ Roquetas, near Tortosa, on the river Ebro, Spain. 

 It is in latitude 40° 19' 14" N. and longitude oh. im. 58-5° 

 E. Its altitude is 51 m. Originally of private origin, it 

 was inaugurated in September, 1904, in connection with 

 the College d 'Etudes Superieures de la Compagnie de 

 Jesus, Tortosa, with the assistance of many private 

 individuals. In October, 1904, it was recognised by the 

 Spanish Government as an establishment of public utility, 

 and, following this, the Government in 1907 made a grant 

 in aid, which is used to defray the cost of the publication 

 of memoirs and bulletins. 



The observatory consists of eight separate buildings, and 

 observations are made in meteorology, solar physics, 

 terrestrial magnetism, electricity, and seismology. An 

 account of the observatory, and also of the observations of 

 the total solar eclipse of 1905, is contained in the first 



NO. 2160, VOL. 86] 



memoir, written by the director. Padre R. Cirera, S.J. _ The 

 second, third, and fourth memoirs are entitled, respectively, 

 " La Observacion Solar," " La Seccion Magn^tica," and 

 "La Seccion Electrica." 



In the solar section, daily photographs of the sun are 

 taken both in integrated light by photoheliograph and in 

 " K " by the spectroheliograph, which is of the Evershed 

 type. This instrument gives a disc of 62 mm. diameter, 

 the primary image being formed by an objective of 

 150 mm. aperture and 2 m. focal length. 



The areas and positions of spots, on the heliograph 

 pictures, and of the flocculi, on the spectroheliograph 

 negatives, are measured and published in the monthly 

 bulletins. 



In the meteorological section, all the usual observations 

 of pressure, temperature, rainfall, winds, and clouds are 

 made with well-known standard instruments three times 

 a day, viz. at yh., i4h., and 2ih. 



The observations of atmospheric potential, ionisation, 

 &c., are undertaken by the meteorological department. In 

 the department of geophysics, the observations of mag- 

 netic values and variations are made, and hourly values 

 are tabulated. A microseismograph " Vincentini " and a 

 " Grablovitz " pendulum are used in the seismological 

 section. The results of all these observations, both tabular 

 and curves, are published in monthly bulletins. 



The first bulletin is for January, 1910, and those for 

 February, March, and April have also been published. 

 The January bulletin contains a short account of the 

 observatory, and accounts also of the methods used in 

 making and reducing the observations. 



Having regard to the amount of work which each 

 bulletin represents, and noting the convenience of having 

 all the different elements registered in one volume, the 

 director. Padre R. Cirera, S.J., is to be congratulated on 

 having been able to issue them so shortly after the making 

 of the observations. M. 



EMOTION AND MORALS. 



ON Saturday afternoon, March ii, a meeting of the 

 British Psychological Society was held at King's 

 College, London, Mr. A. F. Shand in the chair, when Dr. 

 William Brown read a paper on " Emotions and Morals." 

 After a brief survey of the views of earlier writers on the 

 nature and classification of the emotions and their relation 

 to ethics, in which, however, the doctrines of Aristotle 

 and Adam Smith (" Theory of Moral Sentiments ") were 

 treated at some length, the author proceeded to discuss the 

 meaning of the terms " passion," " emotion," and " senti- 

 ment " in relation to the theories of Ribot, Shand, and 

 McDougall. According to ordinary uses of the term, and 

 also to its etymology, passion would seem to indicate an 

 uncontrollable state of mind, in the form either of an 

 actual emotion or a system of emotional tendencies. 

 Although Shand 's employment of the term sentiment to 

 express the conception of " a system of emotional^ disposi- 

 tions centred about the idea of some object " would 

 theoretically cover the latter of these two uses, pa»u>n 

 seems to be a more appropriate and expressive worel ii> 

 indicate those systems which are uncontrollable by the re>i 

 of the mind, and issue, under appropriate conditions, in 

 uncontrollable emotions, e.g. " a passion for politics, " a 

 passion for the stage." 



The word sentiment, as used in literature, has acquired 

 associations of weakness or placidity which constitut.-. a 

 slight drawback to its use in scientific psychology to . ow, 

 all cases included in the technical definition of Shand 

 above-mentioned. "Tender emotion," identified by Ribot 

 and McDougall with the parental instinct, seems to have 

 a wider connotation, and receives more adequate treaiiii>-iii 

 from Shand. In particular, the element of tenderm-s or 

 pathos present in many aesthetic emotions has little con- 

 nection with the parental instinct. 



The question of "emotions and art was tn-abil at 

 some length, with special reference to music and the 

 drama. Neither the sensationalistic nor th(! formalistic 

 theory is adequate as an explanation of music. The 

 ancient Greeks were right in regarding music as " the 

 proper language of the emotions," but it is important to 

 realise that the emotions of music are not, strictly speak- 

 ing, identical with the emotions of everyday life. Tliev 



