The circular device is the Order of The Garter and is in the personal hand of the soveriegn whom she bestows it on.It came about long ago when the king at the time was having a dalliance with a chamber maid and was almost caught by his advisers when they come to have an audience with him.The young lady slipped out just as they came in ,but dropped her garter,the courtiers looked at it the King looked at them and after a pause said"Evil to him that evil thinks" and pulled it up his own leg. That is the translation of the latin.