Attempt to pa:s Helium or Argon through Red-hot Metals. 2t)7 



" An Attempt to cause Helium or Argon to pass through Red- 

 hot Palladium, Platinum, or Iron." By William Ramsay, 

 F.R.S., and Morris W. Travers. Received April 9, — 

 Read May 13, 1897. 



To chronicle experiments which produce no result is a necessity, 

 although not entirely an agreeable one. Whatever the reason of the 

 passage of hydrogen through red-hot iron, and through moderately 

 heated palladium, and platinum — whether it be due to the solubility 

 of the gas in the metal, or to the formation of an easily decomposable 

 compound— neither argon nor helium is able to pass through any 

 one of these metals, even at a fairly high temperature. This would 

 imply their inability to form any compound, however unstable, with 

 these metals, or to dissolve in them at a red heat. Such inactivity 

 is in accordance with their general behaviour, and is still another 

 proof of their inertness. 



The experiment was made in the following manner : — A tube of 

 hard, infusible glass was connected at one end with the reservoir of 

 the gas under experiment, helium or argon. Into its other end was 

 corked a tube of platinum, closed with a palladium cap, or, if iron 

 was the metal under experiment, with a tube of thin wrought iron,, 

 also closed at the end ; the closed end of the interior tube was placed 

 so that it could be raised to a bright red heat by bringing a blow-pipe 

 flame to bear on the hard glass tube. The open end of the metal 

 tube was cemented to a glass tube, attached to a Topler's pump, and 

 provided with a PI ticker's vacuum tube, so that the spectrum of any 

 gas passing through the metal could be observed. This afforded, at 

 the same time, a most delicate test of the presence of the gas under 

 experiment. The metal tube was exhausted, until green phosphor- 

 escence appeared in the vacuum tube, and the gas, helium or argon, 

 was admitted into the space between the glass and the metal tube, 

 at atmospheric pressure. The glass tube was then heated to the 

 highest temperature attainable with a blow-pipe — perhaps 900° or 

 950° C. In no case, whether the metal tube consisted of palladium, 

 platinum, or iron, was there the smallest transpiration of gas, even 

 after half an hour. The phosphorescent vacuum remained in all 

 experiments quite unimpaired. 



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