464 SCIENCE PROGRESS 



out the quantum theory. The note of criticism was sounded by Prof. W. L. 

 Bragg, who drew attention to the remarkable evidence derived from the 

 Xrav examination of crystals in favour of Langmuir's theory of atomic 

 structure. This theory demands electrons in stationary or nearly stationary 

 poiidons with respect to the nucleus, and is thus fundamentally opposed to 

 the Bohr view. Dr. A. E. Oxley laid stress upon the fact that the Bohr 

 theory does not fit in with the magnetic properties of hydrogen. This point 

 was dealt with more fully in his subsequent paper. Mr. C. G. Darwin dwelt 

 on the difficulties in the way of reconciling the rival theories of Bohr and 

 Langmuir, but was hopeful regarding ultimate agreement. 



The Report of the Seismology Committee was then taken. Mr. J. J. Shaw 

 described the work which has been proceeding at Oxford, particularly in 

 relation to the almost continuous occurrence of Microseisms, or small tremors 

 of the earth. First steps have been taken in order to measure their rate of 

 propagation and to elucidate their origin. 



Sir O. Lodge read a paper entitled " Controversial Note on Popular 

 Relativity," and in the discussion which followed Mr. A. A. Rqbb and the 

 President took part. Neither side was, however, convinced. 



On the last day of the meeting, August 27, there were numerous papers. 

 Prof. S. Chapman read a paper on Terrestrial Magnetism and kindred 

 subjects. He showed how both the sun and the moon, by producing atmo- 

 spheric tides, give rise to air currents, which cut the earth's vertical 

 magnetic field and produce electromotive force. When the air is ionised 

 currents are developed, leading to changes in the magnetic field. Both lunar 

 and solar effects are diurnal, and theory fits in well with observation. Mag- 

 netic variation is greatest at periods of the year when the sun's altitude becomes 

 great, in which case there is greater ionisation. This type of ionisation is 

 due to non-corpuscular radiation. In magnetic storms, however, it appears 

 that the ionisation is due to corpuscular radiation proceeding from definite 

 spots on the sun, the storm recurring with the sun's rotation on its axis. The 

 theory also gives an explanation of aurorae. 



The next paper was by Dr. A. E. Oxley on Magnetism and the Structure 

 of the Atom. The author pointed out that hydrogen is found experimentally 

 to be diamagnetic, although, according to Bohr's theory, the hydrogen mole- 

 cule in the liquid state should be paramagnetic to the same extent as nickel 

 at ordinary temperatures. He therefore regards Bohr's theory as radically 

 wrong, and proposes an atomic structure in which the electrons execute small 

 local circuits, the atoms being bound together in molecules by eletromagnetic, 

 instead of electric, attraction. On this view it would be unnecessary to 

 depart from Newtonian mechanics. Prof. A. W. Porter, in the discussion, 

 pointed out that the production of spectra must not be left out of account. 

 The correct solution will be one which is consistent with all the experimental 

 evidence. 



Mr. A. T. DooDSONgave the Report of the New Committee on Tides, dealing 

 with the work in connection with tidal prediction at the Liverpool Tidal 

 Institute. Apparently the Kelvin tide-predicting machines do not give the 

 accuracy demanded by modern shipping. These demands are for an error 

 no greater than 3 inches. Actual variations amounting to i foot occur, 

 particularly in shallow waters, and the origin has not yet been detected. 



Mr. J. H. Shaxby read a paper on Vapour Pressures, in which he indicated 

 a modification of Dieterici's equation which, without the addition of a new 

 constant, gives a closer approximation to observation. 



There were also papers by Dr. P. V. Wells on The Thickness of Stratified 

 Soap Films, and by Mr. H. P. War an on A New Type of Interferometer , an 

 ingenious modification of the Lummer plate, the glass slab being replaced by 

 a layer of water or other liquid floating on mercury. 



The proceedings terminated with a vote of thanks to the President. 



