AMERICAN GEOLOGISTS AND NATURALISTS. 51 



reports, resembling those produced by blasting rocks, which might 

 have been heard ten or twelve miles. The height of this berg was 

 estimated by Mr. C, at from fifty to seventy feet, and its length at 

 fom- hundred yards. While examining it through the glass, it was 

 observed to incline suddenly more than usual, and in the next mo- 

 ment, with a crash and roar that were truly fearful, and amid a 

 whirlwind of spray and foam, the whole enormous pile rolled over 

 on its side, tearing up with it, no. doubt, large quantities of matter 

 from the bottom, and loading the sea with mud and sand for more 

 than a mile in all directions from its bed. 



April 27, 1829, Mr. C. passed, in lat. 36° 10' N. Ion. 39° W. near the 

 middle of the Gulf Stream, which there set in an east-south-easterly 

 direction, an iceberg, estimated to be a quarter of a mile long, and 

 from eighty to one hundred feet high. It was much wasted in its 

 upper portion, wliicli was worn and broken into the most fanciful 

 shapes, forming resemblances of minarets, spires, pyramids and cas- 

 tellated ridges, whose character was momentarily changing by rea- 

 son of the berg moving backward and forward horizontally with great 

 quickness. A strong breeze, and numerous smaller fragments of ice 

 floating in its vicinity, prevented a very near approach, but on one 

 side, a large earthy colored patch was seen, having numerous blacker 

 spots, which Mr. C. had no doubt were bowlders, scattered over it. 

 Some of these presented a surface of two or three hundred square 

 feet. 



In 1831, on a passage from Boston to Mobile, at daylight of 17th 

 August, in latitude 36° 20' north, longitude 67° 45' west, upon the 

 southern edge of the Gulf Stream, Mr. C. fell in with several small 

 bergs in such proximity to each other, as to leave little doubt of their 

 being fragments of a large one, which, weakened by the high tem- 

 perature of the surrounding water, had fallen asunder during a strong 

 gale which for several days previous had prevailed from the south- 

 east. The natural tendency of this would be to force the berg into 

 the warm northeast current of the stream, where, already much worn 

 by its prior sojourn there while crossing from the north, its separation 

 soon took place. The strong northwest wind immediately following 

 the southeast gale, probably drove the fragments out of the Gulf 

 again, to where they were seen in the eddy current, which Mr. C. 

 found to set in that place southwest, at the rate of half a mile per 

 hour. And here, said he, a suggestion of much geological interest 

 presented itself to his mind. Supposing an iceberg of the present 

 day to break loose from the northern polar regions, loaded with blocks 

 of stone and gravel, and drifting southward, to strand upon the Banks 

 of Newfoundland, or George's bank near our own shores, and there 

 remain for a considerable period grinding itself upon the ocean's 

 bed, thereby incorporating into its mass, portions of it, such as 

 shells, gravel, sand, clay or stones. OAving to the unequal action of 

 the weather upon its surface, and of water on its submerged portion, 

 it might, as has been shown, turn partially or even entirely over, thus 



