444 Prof. Ramsay and Mr. Travers. The Gaseous 



'- Malacone, ZrS0 4 , from Hitteroe in Norway, was the only mineral 

 in which argon was found. Five grams of the mineral gave 12 c.c. 

 of gas unabsorbed by caustic soda. After explosion with oxygen, 

 and absorption of the residual oxygen with phosphorus, about Ol c.c. 

 of gas remained. The residue was introduced into a tube with 

 aluminium electrodes which was sealed off from the pump and 

 attached to a coil giving a discharge sufficiently powerful to heat 

 the electrodes to a red heat. The nitrogen was quickly absorbed by 

 the red-hot electrodes, and, as soon as the banded spectrum had dis- 

 appeared, the lines of helium and argon became visible. The green 

 line of the helium spectrum was very strong, and the glow in the- 

 tube was distinctly green. 



The argon present was in too large quantity to be attributed to- 

 accidental leakage of air into the apparatus ; but, in order to confirm 

 this exceptional result, and also to determine whether the green effect 

 in the tube was due entirely to the low pressure of the helium, the 

 experiment was repeated with a larger quantity of the mineral. 

 With 10 grams of the mineral a quantity of gas was obtained, 

 which, after removal of nitrogen, gave a yellow glow in the vacuum- 

 tube ; argon was again present, and its second spectrum could be 

 brought out very strongly by means of a jar and a spark-gap in the- 

 secondary circuit. The experiment was repeated a third time with 

 the same result. This proved conclusively that inalacone contains 

 both argon and helium. 



Cinnabar. Five grams gay e 0*5 c.c. of gas, which consisted only of 

 carbon monoxide. 



Cryolite. 7*6 grams gave only a minute bubble of carbon mon- 

 oxide, 



Apatite. Six grams gave O5 c.c. of a gas consisting wholly of 

 hydrogen and carbon monoxide. 



Baryta-celestine. No gas was evolved; the pump remained at a 

 phosphorescent vacuum. 



Serpentine. This specimen was from the Riffelhorn, and has been 

 analysed by Miss Aston ;* 5 grams gave 4 c.c. of gas which consisted 

 wholly of hydrogen. 



Gneiss, from the Diamirai Glacier, directly below the peak of 

 Nanga-Parbat, Kashmir, brought home by Dr. Collie : 3 grams gave 

 6 c.c. of hydrogen. 



Scapolite, a silicate of calcium, magnesium, and aluminium, gave 

 no gas. 



Cobalt ore, containing a considerable quantity of manganese 

 dioxide: 3'2 grams of mineral, heated alone, gave 35 c.c. of gas- 

 consisting wholly of oxygen. 



* ' G-eol. Soc. Journ.,' 1896, p. 452. 



