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 ome 
as but it acted like soft iron. 
- That the brass was not magnetic by inne containing iron, was 
tides 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- 
ation of the instrument shall be obtained. 
Cincinnati Female Academy, Oct. 20th. 1832. 
Arr. V.—Facts relating to Divan Action; by the Hon. Wx. 
A. THompson. 
FO PROFESSOR SILLIMAN. 
es Sir-—When’ I had the pleasure of seeing yee: at New 
ivan 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 asI 
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. xvi, p. 408 of your Journal. I have examined this part of 
the State with considerable care, and have found that in more than 
ity different places where I have seen the solid strata, the grooves 
ind furrows appear from an inch to one fourth of an inch deep, and 
fom one fourth of an inch, to three and four inches wide; and in 
ome cases they run due north, and in every direction pa north 
© twenty five degrees south of east. I have found them also i 
6s J @ fh ot 
