: Other powers that the Nine and Seven possessed included "rendering visible the unseen" (apparently this means the Elves wanted to be able to make wraiths appear visible to living eyes), and enhancing the natural powers of the wearers. The Three did not confer invisibility, but they did help to hold back Time, and Elrond said that all the Rings were intended to help with healing, making, and understanding. So the Three would have possessed these abilities, and they were apparently more powerful than the Seven and the Nine.

I assume (perhaps incorrectly) that Elrond used Vilya to heal Frodo's wound from the Nazgul attack, since it was beyong any healing that Aragorn could accomplish (and he had vast powers of healing). Is this, then, the reason for Frodo's recurrent problems with the "old wound" later, as the rings and everything acheived by them had begun to fade?

-RobRoy