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It is written in the Silmarillion , in the chapter "Of the coming of Men into the West", p. 168:
        "Now the Eldar
      were beyond all other people skilled in tongues; and Felagund" 
              (King Finrod Felagund
      of
      Nargothrond
      who eventually died fulfilling an oath to 
              Barahir, Beren's
      father, 
      when he followed Beren into Thangorodrim and there fell 
              into darkness and was
      slain
      by
      a werewolf, even as he slew it, but I digress.) 
              "discovered also that
      he
      could
      read in the minds of men such thoughts as they wished 
              to reveal in speech." 
    This passage is omitted in all other
      versions of the "Quenta Silmarillion", but as the Silmarillion
      was
      later then these I would take it to be true. Whether this ability
      was
      given to all elves, all the Noldor or only the high among the
      Noldor or
      other Races
      is not known to me. 
          It was said (Lord of the Rings) that
      Galadriel
      could
      read the hidden secrets of men's hearts.  It would appear
      that if
      she
      had this ability it was augmented by her Ring, one of the Three,
      (Nenya),
      for she was able to read the hearts of Gimli and Legolas as well (The
Fellowship
        of the Ring: "The Mirror of Galadriel".). 
          The Orcs are but perverted versions of elves so
      likely
      if they have it normal elves do.  It would appear they don't
      for
      they
      had to torture Frodo and others (LOTR) In order to make them
      talk. 
      Whether as Varda (guild member, not book character)
      suggested, 
      it's
      strength might depend on whether the mind readee was fond of the
      mind
      reader,
      would also help to decipher this mystery were it known.  I am
      forced
      to conclude from the limited information that it is not known who
      had
      it,
      what was the extent of the ability, and what it depended on. 
      I
      leave
      it up to you, the reader, to decide for yourself. 
    
References: 
          Lord
        of
        the Rings : FotR
      "The Mirror of Galadriel"
          Silmarillion
      "Of the coming of Men into the West"  
Related articles: See also the ability of prophecy
      under 
          "Mythological Themes in the Works of Tolkien"  by
      Irmo-(Valar)
      (Ed. note: paper removed at
        Irmo's
        request)