GEOLOGY. 235 



stones and ashes. This matter, impelled by the action of the wind, 

 was spread through the whole district of Kadoe, and also those of 

 Djokjakarta and Surakarta. At several points the soil was covered 

 with ashes to the depth of three inches. The river of Blongkeng 

 was almost wholly filled up, and it is feared that its waters must 

 overflow in the rainy season. The inhabitants fled and no life was 

 lost; but the loss of property, including crops of rice, tobacco, and 

 indigo, with whole fields of com, was immense. 



OBSERVATIONS ON THE OLD CRATER OF KILAUEA, SANDWICH 



ISLANDS. 



THE following observations on the old crater of the volcano Kilauea, 

 Sandwich islands, were communicated to Sillimarfs Journal for March, 

 by Rev. C. S. Lyman : " The old crater is a pit a mile in diameter, 

 and five or six hundred feet deep, separated from the present active 

 crater by an isthmus of earth, about a quarter of a mile in width. 

 The bottom is covered with lava in thick strata, resembling ice in the 

 bottom of a pond after the water has been drawn out. This covers 

 an area three quarters of a mile in diameter, and rises around the sides 

 of this bowl-like concavity some forty or fifty feet above the level 

 of the bottom. Projecting perpendicularly from the bottom are great 

 numbers of stone pillars of various sizes, from one to two feet, and 

 of heights from one to twenty feet. . These pillars are tubular, and 

 filled with charcoal. The origin of these pillars I take to be this. 

 At some comparatively recent period, the lava burst out far up the 

 sides of this pit, and even upon the neck of land between the two 

 craters, and flowed down into the bottom, at that time a forest, 

 filling it up to the depth of forty or fifty feet with a lake of lava. 

 The lava in contact with the trees would be cooled at once into an 

 incaseinent of stone, from two to six inches in thickness, while the 

 rest of the mass remained fluid. The trees would of course be almost 

 instantly reduced to charcoal, and a crust often a foot or so in 

 thickness must have cooled on the surface of the lake. The lake must 

 then have been drained oif subterraneously, while the crust, descend- 

 ing, like the ice on a pond when drawn off, would be pierced by these 

 solid encasements of the trees, and finally lie scattered over the 

 bottom in huge cakes, as ice would among stumps on the bottom 

 of the pond, leaving these curious tree-encasements projecting as they 

 now do." 



CURIOUS EFFECTS OF TRAP DIKES ON MAGNESIAN LIMESTONE. 



IN the Philosophical Magazine, some curious effects of the intersec- 

 tion of magne^ian limestone beds by dikes of greenstone, occurring in 

 the island of Bute, are described by Mr. James Bryce. The limestone 

 is rendered saccharine in texture, having a crumbling character adjoin- 

 ing the dike, but hard a short distance off. By analysis it was found 

 that the unaltered rock contained twenty per cent, of carbonate of 

 magnesia, while the part altered by the dike contained only from one 



