I believe Col. P. C. Bethel was an old time resident of the area and not involved with the present conflict. Perhaps a veteran of previous wars, 1812, Mexican, etc.

I have been unable to ID Major Brown.

Official records of the Union and Confederate Navies in the War of the Rebellion. ; Series I - Volume 19: West Gulf Blockading Squadron (July 15, 1862 - March 14, 1863) p. 523
http://ebooks.library.cornell.edu/cgi/t/text/text-idx?c=moawar;cc=moawar;type=simple;rgn=full%20text;q1=Cornay;firstpubl1=1880;firstpubl2=1922;view=reslist;subview=detail;sort=occur;start=1;size=25;didno=ofre0019