Reading it opens a window to select the skill a player wishes to advance - "Choose the stat you wish to be advanced!" After confirming - "You read a fascinating chapter and earn experience! You have been awarded 2,000 (skill) experience!" After the third reading: "The book crumbles into a dust cloud of knowledge."
It cannot be dropped, but rather destroyed. If it is lost, you can get another tome from Veliaf in Burgh de Rott.