FEB. 4, 1923 SCIENTIFIC NOTES AND NEWS 47 
The complete paper will be published in the near future. 
Mr. R. B. SosmMan prefaced his paper on Theory of the structure and poly- 
morphism of silica, by an informal communication describing an Improvement 
on Whitlock’s method of constructing models of crystal structure, in which glass 
rods carrying the “atoms” are replaced by threaded brass rods. The paper 
was discussed by Mr. Wurtn. 
Author’s Abstract: There exists a wide variety of experimental data on 
the forms of silica, and particularly on quartz, which have never been assem- 
bled and explained on the basis of a single consistent set of hypotheses as to 
the ultimate structure of this substance. The author has attempted to 
provide such a set of hypotheses, based upon the general knowledge already 
gained concerning the structure of matter in general and silica in particular. 
It is believed that the silica atom-triplet maintains a certain degree of indi- 
viduality in its amorphous and crystalline states as well as in its compounds, 
and the freedom of its oxygen atoms to change their positions with respect 
to the silicons is restricted. The triplets are assumed to assemble into chains 
or threads in the liquid and glassy states, and a thread structure persists 
in the crystalline states (cristobalite, tridymite, chalcedony, quartz). The 
high-low, or alpha-beta inversions in all the forms are thought to be due to 
the same underlying change, namely, a change in the state of motion of some 
subsidiary part of the atom-triplet, perhaps a pair of revolving electrons; 
this change results in an alteration of the relative positions of the two oxygen 
atoms attached to a silicon atom. Analogous phenomena of polymorphism 
are indicated in the silicates and in the dioxides of the other elements having 
an external electron structure similar to that of silicon (titanium, zirconium, 
germanium, tin). The paper will be published in full in the Journal of the 
Franklin Institute. 
All three of the above papers were illustrated by lantern slides, and Mr. 
SosMAN also showed models. 
H. H. Kimsatu, Recording Secreiary. 
SCIENTIFIC NOTES AND NEWS 
Dr. J. 8. Amss, professor of physics, Johns Hopkins University, gave the 
first of a series of lectures on the Quantum Theory at the Bureau of Standards 
on January §, 1923. It is the aim of this series of lectures to give a broad 
survey of the Quantum Theory to those unfamiliar with it, the final lectures 
to be given by Dr. A. Sommerfeld. 
In his lecture Dr. Ames showed just where the hypothesis was introduced 
into physics. This was in the case of radiation from a black body, where 
the equations derived by methods based on classical mechanics were at 
variance with experiments. Planck made a modification, proposing that the 
energy vary by steps or by “quanta” hv, where v is the frequency of the 
radiation and h is a universal constant. This gave a law which agreed with 
experiment. That is, the theoretical black body was closely approximated 
in practice and the energy of the emitted radiation over the entire spectral 
range agreed in amount with that calculated from the radiation law. 
A relation for the specific heat of a substance was derived as a function of 
temperature and hv, thus involving the hypothesis. The calculated and 
experimental values of those parts vital to the hypothesis were in agreement. 
The mathematics essential to the development of two laws was given in 
the lecture. Dr. Ames emphasized that the Quantum Hypothesis rests on 
