202 Scientific Intelligence — Geology and Mineralogy. 



consiiij Illinois, and Indiana. In Northern Michigan they are still 

 more frequently met with. 



The great transported mass of native copper on the Ontonagan river, 

 so frequently alluded to by travellers, and which he, Dr H. estimated 

 to contain about four tons of native metal, was stated to have all the 

 characters of the other loose masses referred to. 



The source of these transported masses has hitherto been somewhat 

 obscure, although there has been good reason to believe, that most of 

 them had their origin from the trap-rocks; but whether from true veins, 

 or from the mass of the rock itself, was not known. He said, that, after 

 examining the country with care, he was enabled to state, that, with, 

 out doubt, a very considerable portion of them had their origin from 

 what may be regarded as true veins. 



Those which were regarded as true veins, were uniformly noticed to 

 originate in the trap-rock, but they were frequently traced across the 

 superimposed sedimentary rocks, including the red sandstone. The 

 direction of the veins across the upper rocks most frequently corresponds 

 to the dip of those rocks. — American Journ. of Science, vol. xli. No. i. 

 p. 184. 



3. The Great Crater of the Volcano in Hawaii.''' — " It is an immense 

 pit, one thousand feet deep, and six miles in circuit, with perpendicu- 

 lar walls, except at one point, v/here it is reached by a deep descent, 

 and the whole of this vast cauldron full of boiling, bubbling, and spout- 

 ing lava. The surface at one moment as black as ink, and the next 

 exhibiting rivers, and pools, and jets of a hideous blood-red fluid, that 

 was sometimes thrown up to a height of fifty or sixty feet, and fell 

 back with a sullen plashing that was indescribably awful. The aspect 

 of the whole was hellish — no other teim can express it. By night it 

 was grand beyond description. The frequent lightings up, the hissings, 

 and deep muttering explosions reminded me of some great city in 

 flames, where there were magazines of gunpowder or mines continually 

 exploding. Vesuvius is tame in comparison with it. Just previous to my 

 visit the lava had burst out at a new place, about six miles north-east of 

 the crater, and flowed down to the sea in a stream o^ forty miles in length 

 by from one to seven in breadth. I saw the light one hundred miles 

 off. It reached the sea in five days ; threw up three hills of from one 

 hundred and twenty to two hundred and fifty feet high ; gained two 

 thousand feet out seaward from the old line of coast by three-fourths of a 

 mile in width, and heated the water for fifteen miles on either side to 

 such an extent that the fishes were heaped up in myriads on the shore, 



* In a letter to Professor Silliman, dated Honolulu, Oahu, Oct. 24, 1840. 

 — Silliman's Journal, vol. xli., p. 200. 



