proceedings: geological society 193 



solely to the atom nucleus. This means that to explain chemical union 

 one must assume either that Coulomb's law does not hold for the total 

 (resultant) electrical force acting on an electron in a molecule, or else 

 that the electron is such that other than purely electrostatic forces can 

 act on it. At the point of equilibrium there is acting on a valence elec- 

 tron a restoring force which measures the. stability of the electron ar- 

 rangement, i.e., the "reactivity" of the compound. The magnitude of 

 this restoring force, as determined by valence considerations and as 

 checked by information furnished by the visible and ultra-violet absorp- 

 tion spectra, shows that an arrangement of eight and not six forms the 

 most stable grouping of electrons around the positive nucleus. This 

 can not be explained on any plane model of the atom, as this grouping 

 requires lack of radial symmetry in the electron or nucleus. Saturnian 

 atom models are inadmissible. Either they will radiate energy at the 

 absolute zero (contradicting thermodynamics) or else they can not radi- 

 ate at all. New physical assumptions are needed to construct a suc- 

 cessful atom model, as one can not be deduced from the ordinary solu- 

 tions of Maxwell's equations, these solutions being incompatible with 

 the properties of the positive nucleus as well as with its very existence. 

 The static model of the atom is preferable as, although it requires new 

 and startling assumptions about the nature of the electron and the 

 positive nucleus, these assumptions need not contradict the classical 

 theories of phj^sics. 



Informal communications. Messrs. W. W. Coblentz and W. B. 

 Emerson presented to the Society a Preliminary note on the selective 

 reflection of tungsten. The spectral radiation curves of incandescent 

 tungsten filaments show peculiarities indicating the possibility of se- 

 lective emission due to minima of reflection. The reflectivity curves 

 of various metals, e.g. gold and copper, have in the visible spectrum 

 indentations which give rise to strong selective emission in the incan- 

 descent metal. An examination of the spectral reflecting power curve 

 of tungsten (in the form of plane highly polished mirrors) shows a small 

 indentation at about 0.85 n, which is greater than can be accounted 

 for at present as being due to experimental errors. This depression in 

 the reflectivity seems to be a property of the pure metal. 



On account of the lateness of the hour, formal discussion was omitted. 



Donald H. Sweet, Secretary. 



THE GEOLOGICAL SOCIETY OF WASHINGTON 



The 313th meeting was held at the Cosmos Club, January 10, 1917. 



INFORMAL COMMUNICATIONS 



J. S. Diller: More evidence as to the high temperature of the late erup- 

 tion of Lassen Peak. 



REGULAR PROGRAM 



George Otis Smith: Geology and public service. (Published in The 

 Scientific Monthly, February, 1917.) 



