Facts relating to Diluvial Action. 243 



Bright red. So great was the magnetism of some of the brass of my 

 compass, that it would attract the test needle more than one eighth of 

 an inch, and by contact would carry it 70° out of the meridian. 

 I was obliged to anneal the whole box. I did not find it to possess 

 polarity, but it acted like soft iron. 



That the brass was not magnetic by actually containing iron, was 

 evident by its magnetism being destroyed by annealing. It might be 

 well to make the spring of silver. It is possible that this application 

 of the lens and reflector to the compass is not new ; but so far, I 

 have not been able to find an account of any thing similar. Notice 

 of the invention has been communicated to the Patent Office of the 

 United States. A patent will be applied for as soon as the best modi- 

 fication of the instrument shall be obtained. 

 Cincinnati Female Academy, Oct. 20th. 1832. 



Art. v. — Fads relating to Diluvial Action; by the Hon. Wm. 



A. Thompson. 



TO PROFESSOR SILLIMAKT. 



Dear Sir. — When I had the pleasure of seeing you at New 

 Haven, last autumn, I intimated my intention of sending you my 

 views of the geological features of Sullivan County, New York, 

 and likewise the traces of diluvial action on the solid strata, with 

 some of the proofs that present themselves, in every part of the 

 country where the earth has been removed, so deep as to come 

 to firm rock, below the effects of frost and other decomposing 

 agents ; but, the snow came on so early in the fall and my health 

 has been so indifferent, this spring, that I have been obliged to de- 

 fer it until the present time. Perhaps I shall not even now be able to 

 write any thing new or interesting on this subject, especially as I 

 find that Sir James Hall, many years since, described traces of 

 diluvial action in Scotland, and Mr.' David Thomas of Cayuga has 

 made similar observations in the western part of this State as appears 

 in Vol. XVII, p. 408 of your Journal. I have examined this part of 

 the State with considerable care, and have found that in more than 

 fifty different places where I have seen the solid strata, the grooves 

 and furrows appear from an inch to one fourth of an inch deep, and 

 from one fourth of an inch, to three and four inches wide ; and in 

 some cases they run due north, and in every direction from north 

 to twenty five degrees south of east. I have found them also in the 



