Captain John Rippey's service in the Pennsylvania militia is a little fuzzy to me. I've seen claims he served with Washington at Valley Forge, claims which I don't think are true. I've run across, and promptly lost track of, references to his involvement in logistics and possibly to his involvement with guarding prisoners. What prisoners you ask? First the Battle of Saratoga, where General Burgoyne surrendered (the "Convention Army") and later from the Battle of Yorktown where General Cornwallis was commander.
Anyhow in 1781 the Convention Army was marched from Albemarle, VA to the York area. The local militia would have been involved in guard duty and management of the prisoners.
June Lloyd at Universal York has posted in the past on Camp Security and now has another post on it. She's done work in the Archives and found an interesting record from one of the guards. (Not Capt. Rippey.) Here's a site devoted to it.