TRANSACTIONS OF SECTION A. 713 
SATURDAY, SEPTEMBER 19. 
The Section was divided into two Departments. 
The following Reports and Papers were read :— 
DeEpaRTMENT I.—Puysics. 
1. Report on the Comparison of Magnetic Standards. 
See Reports, p. 87. 
2. Report on the Comparison and Reduction of Magnetic Observations. 
See Reports, p. 231. 
3. Adjourned Discussion on Professor 8. P. THompson’s Paper on the 
Relation between Kathode Rays, Réntgen Rays, and Becquerel’s Rays. 
4. On Hyperphosphorescence. 
By Professor Strvanus P. Tuompson, D.Se., FAS. . 
This phenomenon, discovered by the author independently at the same time 
with M. Henri Becquerel, consists in the persistent emission by certain substances, 
notably by metallic uranium and its salts, of invisible rays which closely resemble 
Réntgen rays in their photographic action, and in their power of penetrating 
aluminium, and of producing diselectrification. 
The author finds the order of transparency of substances to be different for 
these rays from that which exists for Réntgen’s rays. He has also observed 
photographic action through opaque screens of paper by light emitted from phos- 
phorus slowly oxidising in air. The hyperphosphorescence of uranium in the 
metallic state is about equal in darkness and when exposed to light, but with 
‘aranium nitrate the continued stimulation of light promotes the emission of these 
xays. No similar rays exist either in are light or in sunlight as observed in 
London. 
5. Observations on the X-Rays. By H. H. F. Hyypmay. 
6. On the Component Fields of the Earth's Permanent Magnetism. 
By Dr. L. A. Bauer. 
7. On a One-Volt Standard Cell with Small Temperature Coefficient. 
By W. Hispert. 
The author and Mr. Sewell have worked for two years dt improving a cell first 
made by Helmholtz. The elements are zinc and mercury, in a solution of chloride 
of zinc. To get a potential difference of one volt the solution must be pure, and 
have a density of about 1:380, 
1896. 
3A 
