XXXVIIl. ABSTRACT OF PROCEREDINGS. 
The electrons in an atom may be supposed to arrange themselves in a 
similar manner and on this view the periodic law, and the laws of 
chemical combination have received a physical explanation. 
2. ‘“ Photographs of stages of the development of the electric 
arc,’ after the circuit has been broken and restored 
without movement of the carbons. 
3. ‘ Photographic records,” shewing the diurnal periodicity in 
the spontaneous ionisation of air within an hermetically 
sealed vessel. 
4. “ Lightning conductor crushed by the discharge,” pre- 
sented to the Physical Laboratory by H. G. Clark, Esq. 
. “A form of radium clock.” 
n 
6. “Illustration of the ordinary method of comparing the 
radio-activity of minerals. | 
. “Wilson’s experiment,” showing the effect of Roéntgen rays 
in promoting the formation of clouds when air is suddenly 
expanded. 
a | 
8. “A modified form of Sprengel vacuum pump.” 
g. ‘‘ Glass plates for testing the flatness of surfaces by optical 
means. 
Mr. W. J. Ciunizes Ross, B. Sc., Lecturer in Chemistry, 
Technical College— 
“Deposits”? formed by placing crystals of salts in silicate of 
soda solution (water glass). Each salt shows a charac- 
teristic form of growth. 
(Mr. Ross recently brought this phenomenon, which is new to Aus- 
tralian scientific men, and perhaps altogether new, under the notice of 
the Society.} 
“Colloidal Gold.” The gold is in the metallic state, the 
particles are believed to be about yoosscoo inch in 
diameter. 
THe Roya Society or N.S. WaLtes—Exhibits formerly the 
property of Professor Faraday. 
‘‘One piece electrical apparatus. Native silver. Iridesent 
antimonite. Clausthalite (Selenide of Ag. and Pb.). 
Barium peroxide, BaO,, One piece of glass made by 
Faraday. Kod of antimony.” 
These interesting exhibits were the gift of Professor Liversidge. 
es 
