Pick up and Elder Scroll, but also don't forget to pick up the Blank Lexicon from the receptacle. Press the fifth button from the receptacle once.Press the fourth button from the receptacle until the lenses over the dwarven machine line up.Press the second button from the receptacle a few times until the receptacle lights up.Place the Blank Lexicon on the Lexicon Receptacle.Once you're inside, follow these steps to solve the Lexicon puzzle: Septimus will give you everything you need, including the Blank Lexicon item, to reach the Tower of Mzark located south of Dawnstar, The Pale (see map above for the exact location). He will direct you to Septimus Signus' Outpost in Winterhold, where you can speak to Septimus Signus about the Elder Scroll. Once inside the college, find Urag gro-Shub, the librarian of the Arcanaeum. There you need to persuade Faralda to let you enter the college by showing one of your dragon shouts. Speaking to either NPC will let you continue the quest, as both will direct you to the College of Winterhold. After doing so, you will have to speak to one of two other NPCs: The Elder Knowledge main quest and your path to the Lexicon puzzle begins at the Throat of the World, Whiterun, where you can speak to dragon Paarthurnax and ask him about the Elder Scroll. How to Solve the Lexicon Puzzle Travel to the Tower of Mzark

The long journey will take you to a secret location inside the Tower of Mzark, an ancient Dwemer ruin, that holds a dwarven machine, on which you'll need to push certain buttons to solve the Lexicon puzzle and reveal the Elder Scroll.

How to activate the lexicon receptacle