[Brian Williams]

I have had this knife since I was in grade school in the 60's, it was owned by one of my uncles and I was wondering if anybody knew when it was made etc.http://www.gunpix.com/gallery/Miscellaneous_and_Oddities/camilus%20knife.jpg

[Harbinger]

Best I could guess from those markings, is somewhere from 1902 through WWII. Kinda vague, huh? :D
After WWII, Camillus mainly used the Camillus/New York/USA markings, along with a million contract name companies, and two million of it's own brand names and stamps. Quite the popular company. :)
Sorry I can't narrow it down anymore.

[hso]

It's a Camillus version of the famous Marbles Ideal field knife. I'll find out the manufacturing dates and get back to you.