162 AN EXPERIMENTAL STUDY OF RADIO-ACTIVE SUBSTANCES. 



And to what uses is this lioht-oenomting material to be applied? 

 Are our bicycles to be lighted with disks of radium in tin}' lanterns? 

 Are these substances to become the cheapest form of light for certain 

 purposes? Are we about to realize the chimerical dream of the alche- 

 mists — lamps giving light without consumption of oil, perpetually? 



Seriously, in what direction is profound study of these substances 

 going to lead us? Will it not greatly extend our knowledge of phys- 

 ical manifestations of energy and their correlation '. What bearing 

 will this power of ''opening up paths through the air" for currents 

 of electricity have upon our knowledge of heat, light, eloctricity, and 

 those forms of energy called by the names of Rontgen and Becquerel? 



In what corner of the globe will be found the cheap and convenient 

 supply of the raw material yielding the radio-active bodies? Will not 

 chemists be obliged to reexamine nmch known material by laboratory 

 methods conducted in the dark \ Many of us have worked up kilo- 

 grams of pitchblende to extract uranium oxids, and in so doing have 

 poured down the waste pipe or thrown into the dust bin the more 

 interesting and precious radio-active ))odies. 



At all events, whatever the future may bring, physicists are deeply 

 indebted to Becquerel, to Madame and Monsieur Curie, for placing in 

 our hands new methods of research and for furnishing a novel basis 

 for speculations destined to yield abundant fruits. 



POSTSCRIPT. 



Since writing the above an important announcement has l^ccome 

 known by the arrival in America of a number of the Berichte der 

 deutschen chemischen Gesellschaft, issued in Berlin May 14, 1900. 



Bela von Leng^'el, of Budapest, has pointed out that the chemical 

 evidence is insufficient to establish the eh^mentary character of these 

 radio-active bodies and claims to have prepared the so-called "radium" 

 syntheticalh'. By fusing with the heat of the electric arc uranic 

 nitrate mixed with 2 or 3 per cent of barium nitrate and treating the 

 mass with nitric acid, water, and sulfuric acid, successively, he 

 obtained radio-active barium sulfate possessing all the ph3'sical prop- 

 erties characteristic of the "'element" announced b}' Madame Curie. 

 The resulting substance gives out actinic rays, Rontgen rays, excites 

 platino-cyanid screens, and causes air to conduct electricity. 



The Hungarian chemist has made and examined the chlorid and the 

 carbonate of this substance and finds they have the same properties. 

 He wishes his paper regarded as a preliminary notice, proposing to 

 continue his researches. 



Admitting that radio-active bodies can be manufactured to order, 

 are we any nearer explaining their mysterious powers ? 



Cosmos Club, Washington, D. C, May 26, 1900. 



