540 



NATURE 



[November 21, 1912 



sphere over the British Isles by means of kites and 

 balloons. All the units employed are based on the 

 C.G.S. system. 



Prof. H. F. Reid has suggested that the initial 

 steps in the movement which gives rise to a great 

 earthquake might be detected by the gradual dis- 

 placement of a series of pillars erected along a line at 

 right angles to a growing fault. Another method of 

 foreseeing the occurrence of an earthquake has been 

 suggested by Dr. C. Davison in a recent paper (Ger- 

 land's Beitrdge zur Geophysik, vol. xii., 1912, pp. 

 9-15). The method depends on the distribution of the 

 preliminary shocks in time and space. In the case 

 of the Mino-Owari (Japan) earthquake of 189 1, it is 

 shown that there was a marked increase in frequency 

 of these shocks along and near the line of the fault- 

 scarp during the four years before the earthquake. 

 During the two years before it, the centres of the 

 earthquakes embraced the whole region of the fault- 

 system, clinging closely to the principal fault-lines. 

 Before the great displacement which causes an earth- 

 quake can take place, the small obstacles to slipping 

 must first be removed. The slips by which these 

 obstacles are removed give rise to the preliminary 

 shocks. The effective resistance to displacement thus 

 becomes equalised throughout the whole fault, so that 

 the main displacement occurs with great rapidity 

 throughout its entire extent. It follows, therefore, 

 that when a fault is being outlined by the epicentres 

 of a number of slight shocks, it is probable that a 

 great displacement throughout the region so outlined 

 will occur after an interval which, as in the case of 

 the Mino-Owari earthquake, may amount to a couple 

 of years. 



For the detection of minor fluctuations of atmo- 

 spheric pressure, differentiated from the general 

 barometric changes, a microbarograph was designed 

 some time ago by Dr. W. N. Shaw and Mr. W. H. 

 Dines, and was referred to in these columns (Nature, 

 vol. Ixxi., December 29, 1904, p. 216). Dr. Yoshida, 

 of Tokyo, claims to have made some improvements 

 in this instrument, and Prof. Fujiwhara, of the Cen- 

 tral Meteorological Observatory, Tokyo, has developed 

 a dynamical and adiabatic theory in connection there- 

 with. The apparatus consists essentially of an air 

 chamber, connected by tubes with a cylindrical vessel 

 containing oil, in which floats a bell-jar. The latter 

 rises and falls with the variations of atmospheric 

 pressure, and an attached pen records the re- 

 sults on a revolving cylinder. A capillary tube 

 serves to damp the effect of the larger and 

 slower movements, only the .smaller and more 

 rapid variations being noted. Prof. Fujiwhara gives 

 a series of equations based on his theory in the 

 Journal of the Meteorological Society of Japan (xxxi., 

 No. 9, 1912). He concludes that the dimensions and 

 mass of the apparatus itself constitute an unavoidable 

 source of error when the barometric variations are 

 extremely rapid. To secure the best results he recom- 

 mends that the apparatus be small, and the bell-jar 

 and its attachments of the lightest material, e.g. 

 aluminium. 



NO. 2247, VOL. go] 



When a liquid jet breaks into drops in the air it 

 is well known that the drops become positively, the 

 air negatively, charged. This effect is utilised in 

 Kelvin's water-dropper as a means of generating elec- 

 tric charges, and in electrical measurements in the 

 atmosphere to bring the instrument used to the same 

 potential as the air at a point. The exact nature of 

 the process by which the charges are produced is, 

 however, unknown. The recent work of Dr. von 

 Bernol^k, of the University of Heidelberg, which 

 appears in the Annalen der Physik for October, indi- 

 cates that the production of the charge is intimately 

 connected with the formation of very small secondary 

 drops which accompany the primary drops. If the 

 number of secondary drops formed is increased by 

 producing large primary drops rapidly from a tube 

 the lower end of which is widened, the total amount 

 of charge produced is considerably increased. 



The Electrical Review for November 8 devotes three 

 articles to the openings which China offers to 

 engineers generally and to engineering manufacturers 

 in particular. The latter are strongly urged to send 

 out at once capable engineers as agents in order to 

 grasp an opportunity which will pass rapidly away. 

 One of the articles is by Prof. C. A. M. Smith, of 

 the University of Hong Kong, and deals with the 

 foundation and the aims of that University. From 

 the statement of Sir F. D. Lugard, the Governor of 

 Hong Kong, it appears that in the first instance 

 engineering and medicine are to be the principal 

 applied sciences taught there, while an arts course 

 will afford an opportunity to Chinese students of 

 making themselves well acquainted with English. A 

 dispatch from the Viceroy of Canton to the chief 

 officials of the Chinese Government under him is 

 quoted by Prof. Smith, and from it we gather that 

 considerable anxiety has been caused in China by the 

 evil results which in some cases have followed the 

 residence in Europe or America of Chinese students 

 under conditions of freedom, to which they are quite 

 unaccustomed in their own country. The new Uni- 

 versity will in all probability intercept this stream of 

 students to foreign countries within the next few years. 

 The drawing and plan in Prof. Smith's article indicate 

 that the University buildings cover an area of 50,000 

 square feet, and occupy a fine site on a hill overlooking 

 the harbour. 



A SECOND edition of Mr. J. P. Johnson's "Pre- 

 historic Period in South Africa " has been published 

 by Messrs. Longmans, Green and Co. The first 

 edition was reviewed in the issue of Nature for 

 August 10, 191 1 (vol. Ixxxvii., p. 183). The most 

 important addition to the new edition is an appendix 

 by Mr. Kcnnard, entitled "The Sequence of the 

 Stone Implements in the Lower Thames Valley." In 

 addition, Mr. Johnson has been able, as a consequence 

 of the lublication by Dr. Peringuey of the material 

 in the Capetown Museum, to extend the scope of the 

 book to the Coast Middens. 



In the 1912 volume of the Transactions of the 

 Leicester Literary and Philosophical Society, which 

 also contains the report of the council and annual 



