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England. They have been ascribed by Professor Hitchcock 

 and others to the action of icebergs pressing laterally against 

 the strata. This theory, however, is no longer admissible, 

 since it is not uncommon to find such curved and looped strata 

 alternating with others that are perfectly horizontal both above, 

 and below ; besides, these peculiar loops and curves are trace- 

 able for too great a distance (several hundred feet) to be the 

 result of a mere lateral action. It has been suggested by Mr. 

 Trimmer, that they are probably the result of masses of ice 

 stranded on the shores, and afterwards buried under sand and 

 mud. In consequence of subsequent melting, the overlying 

 sand and mud would necessarily subside, and, by their sub- 

 sidence, cause such curved outlines as we witness in the drift. 

 This theory is unquestionably the correct one ; and, moreover, 

 its correctness has been experimentally demonstrated. Mr. 

 Edward C. Cabot several years ago buried pieces of ice in the 

 sand of the beach at Beverly. When he came to examine the 

 superincumbent strata after the melting of the ice, he found 

 them contorted and looped in a manner resembling very much 

 the curvatures of the drift strata. It is to be hoped that Mr. 

 Cabot will, at some future meeting, communicate to the Acad- 

 emy the results of his experiments. 



Dr. W. F. Channing exhibited to the Academy two discs 

 of paper from the Boston and New York and Boston and Bur- 

 lington lines of the Bain Telegraph, being the record of the 

 great aurora of the 29th of September. On the evening of 

 that day, the sky was overcast in Boston, but the attention of 

 the telegraph operators on all the lines was early drawn to a 

 remarkable display of electric phenomena. All of the tele- 

 graphic instruments were overpowered by currents of atmos- 

 pheric electricity coming in over the wires, lasting, unlike the 

 usual atmospheric disturbances, for several minutes at a time, 

 and in opposite directions in the early and later part of the 

 evening. The strength of the atmospheric current was gener- 

 ally estimated as about equal to one hundred Grove's elements. 



The instruments of the Morse and House Telegraphs were 



