1894. NATURAL SCIENCES OF PHILADELPHIA. 107 



to be soluble iu acids, although the one under discussion is not. I 

 would, therefore, propose Kauaiite as a name for the new variety. 

 The extremely fine division and the approach to crystallization with- 

 out forming true geometrical solids may suggest the mode of its for- 

 mation. It may, with the exception of the carbonaceous matter, be 

 ejected as volcanic. An objection might be based on the large 

 percentage of water, but we must remember that in some volcanoes 

 water is an almost constant ingredient of their ejectments, and we may, 

 therefore expect to occasionally meet with so-called hydrous com- 

 pounds in the material thrown out. The aluminium may have been 

 distilled by the intense volcanic heat together with the other elemen- 

 tary metals and metalloid sulphur. Coming in contact with the 

 atmosphere, the material was oxydized and quickly precipitated on 

 the cooler surface of the earth, giving no time for the formation of 

 crystals. If corundum is reduced and volatilized by the heat pro- 

 duced in the electrical furnace, we may expect similar results from 

 the enormous heat energy of a volcano. 



Volcanic Stalactites. — That the highly heated and very fluid lava 

 in the crater of Kilauii, as well as in other craters, is occasionally 

 shot up into the air some thirty feet or more, has been reported at 

 various times and has also been observed by the gentlemen before 

 referred to. Such lava iu its descent through the air becomes very 

 porous. If such a highly porous rock have a space underneath, a 

 fresh deposit of liquid lava will trickle through the porous cooled 

 lava, forming as it solidifies the pendent stalactites shown iu Plate VI. 

 These stalactites are about one-fourth of an inch thick and about 

 eight inches long. They show no disposition to form cones like those 

 usually seen in limestone caves. These slender, gnarled, rod-shaped 

 formations are mostly hollow and porous and so brittle that it is diffi- 

 cult to prepare a thin section for microscopical study. The color is 

 usually a deep black, sometimes a part is of a brownish tint, due, 

 probably, to a higher oxidation of the magnetite present. Occasion- 

 ally a gray color is noticed but this is caused by the incrustation of 

 some other substance. To ascertain its probable mineralogical com- 

 position, it was necessary to use the fine powder, imbedding it as usual 

 in balsam. The fragments examined beneath the microscope indicate 

 a glassy feldspar having apparently the characteristic of sanidiue. 

 They contain magnetite in great profusion and also gases, 

 probably air. A dichroic mineral is also recognizable in the mixture, 



