PRfesiDkXT's ADDRESS. CXI. 



that radium is not developed direct from actinium but from a 

 new element, ionium, wliich is found mixed with actinium and 

 has recently been separated from it. It is also shown that the 

 life of radium is much shorter than had been thought hitherto — 

 about 236 instead of 1,100 years. It has also been discovered 

 that helium, neon or argon, is formed from radium emanation, 

 according as it is dry, dissolved in water, or dissolved in a strong 

 solution of a copper salt. A French publication gives the 

 curious history of the so-called N-rays, which M. Blondlot con- 

 sidered, a few years ago, that he had discovered. No less than 

 176 papers were written by different scientists on these rays, but 

 great doubt was always thrown upon their existence, and finally, 

 after the discoverer had declined a test which would probably 

 have been conclusive, it is found that the rays are entirely 

 imaginary, and that the supposed results were due to illusion. 

 In time we may hope to get to the bottom of the facts about this 

 illusive element, which has been chosen as the subject for the 

 Cecil Medal for this year. The solidification of helium, lately 

 announced, seems also to be an illusion, the solidification of a 

 little hydrogen mixed with the gaseous helium being mistaken for 

 the solidification of the helium itself. It must be exceedingly 

 hard to be always accurate in these most difficult and delicate 

 experiments. A great sensation was caused by the statement that 

 diamonds had been made by a chemical process, of considerable 

 size, and strong evidence of its truth was produced, but the case 

 savoured of that of the alchemists who were always on the point 

 of owning fabulous riches, and it seems doubtful if we have yet 

 any artificial diamonds except the minute ones made by various 

 unremunerative processes. The President of the Chemical 

 Section at the British Association delivered an address on the 

 subject of Flame, and insisted much on the little recognised fact 

 that many substances, such as sulphur, arsenic, alcohol, ether, 

 paraffin, and a Avhole host of other compounds become phosphor- 

 escent as they approach their flame temperature, in exactly the 

 same way as phosphorus. The application of the X-rays to 

 ascertain the presence of pearls in the oyster without opening it 



