LUMINOUS SHOWERS. 149 



and ice, offers a wide and promising field for investigation. 

 Here no other dust prevails. Professor Nordenskjbld first 

 found cosmic dust in the North at Spitzbergen. The second 

 discovery, off the Taimar coast, seemed to be in the form of 

 yellow specks lying on the snow. They were at first sup- 

 posed to be diatoraaceous ooze;*® but when placed in the 

 hands of Dr. Kjellman, he pronounced them to be pale 

 yellow crystals, and, curious enough, formed of carbonate 

 of lime. " The Original composition and origin of this sub- 

 stance," says Professor Nordenskjold, "appears to me exceed- 

 ingly enigmatical. It was not carbonate of lime, for the 

 crystals were rhomboidal, and did not show the cleavage of 

 calcite. Nor can there be a question of its being arragonite, 

 because tliis mineral might indeed fall asunder of itself; but 

 in that case the newly formed powder ought to be crystal- 

 line. Have the crystals originally been a new hydrated 

 carbonate of lime formed by crystallizing out at a tempera- 

 ture of ten or twenty degrees above the freezing point? In 

 such case they ought not to have been found on the surface 

 of the snow, but lower, on the surface of the ice. Or have 

 they fallen down from the inter-planetary spaces to the 

 surface of the earth, and before crumbling down have had 

 a composition differing from terrestrial substances, in the 

 same way as various chemical compounds found in recent 

 times in meteoric stones? The occurrence of the crystals 

 in the uppermost layer of snow, and their falling asunder in 

 the air, tell in favor of this view. Unfortunately there is 

 no possibility of settling these questions ; but at all events 

 this discovery is a further incitement to those who travel 

 in the high North, to collect with extreme care, from snow- 

 fields lying far from the ordinary routes of communication, 



