Thanks for your replies. In answer to your question - No, the device is not an hourglass. I had considered that but, finding that a bronze hourglass stood for 10 years service in the Reserves,the hourglass doesn't apply to my Dad's service. My Dad was not in the Reserves and got out of the Navy when his 6 year enlistment was up. Actually, the hourglass device doesn't really look anything like this "I".This "I" device stands alone and I believe the hourglass is inside a border.
DANFS does say the Farenholt earned 11 battle stars but on her website they have paperwork posted out there that says she earned 13. My Dad was transfered off the Farenholt after she earned her first 7.
I do appreciate your looking around for an answer to my questions. If you (or anyone else) ever turns up an explanation of the "I" device I'd love to hear it. I have looked all over the web and at sources outside the web and don't know where else to look. Am really starting to wonder if it was anything official at all.