Take the hand and a beer to the captain of the guards in the Ye Olde Dragon Inn. Give him the beer. He will ramble on, and then, he'll take a look at the hand and simply drop it in his beer, turning it into a beer soaked hand. Go to the Wizards' Guild, just east of the bar, enter if you meet the requirements (66 Magic), or ring the bell to make Zavistic Rarve come out. Talk to him and explain the situation. He will tell you that this is the hand of one of his wizards, Clarence. He'll ask you to see if Bert's working schedule has changed recently.