14 PRESIDENT'S ADDRESS. 



ELECTRICITY. 



I am much pleased to say that the subject set for the Cecil 

 Medal last year, " The Most Recent Discoveries in Wireless 

 Telegraphy," has produced an excellent prize essay, to 

 which I would refer any of those present interested in this 

 branch of science, and I will therefore proceed to my next 

 heading of 



CHEMISTRY. 



The photographing of the paths of the minute particles 

 which form the emanation from radium has been accom- 

 plished by condensing water upon them immediately after 

 their liberation, dense and sharply defined clouds being 

 formed. I am not sure if the B and 7 rays have yet been 

 photographed, but straight radiating threads are visible on 

 similar treatment. It has been found that the air for some 

 distance above the ground contains an appreciable quantity 

 of radium emanation, the supply of which is kept up by 

 exhalation from the soil. Certain radio-active substances 

 have now been tested for several years, with the result that 

 it is found that they vary, some having decreased in activity 

 during that period whilst others showed no appreciable 

 change. From this their duration of life in their present 

 form can be determined. The last determination of the atomic 

 weight of radium is 226' 36, which approximates to previous 

 ones. A new metal, which has been named Canadium, has 

 been discovered in British Columbia. It possesses a brilliant 

 white lustre which is not tarnished by damp air, and quantities 

 up to three ounces in the ton have been found in the rock in 

 which it occurs native in minute grains and also alloyed with 

 other platinum metals. The element Boron has, after many 

 previous attempts, been isolated in a pure form and proves 

 to have some remarkable properties. It is next to the dia- 

 mond in hardness and will scratch corundum, and shews an 

 extraordinary rise in electric conductivity with a slight 



