Completing the Momento chapter 4 walkthrough requires you to reactivate the Inventor's celestial machine by solving three core puzzles: the Grandfather Clock, the Alchemical Desk, and the Star Chart Projector. This guide provides a direct, step-by-step solution for every puzzle, hidden object, and collectible within the Inventor's Study to ensure you can proceed to the next stage of your journey without delay.
The primary objective is to gather three Celestial Orbs, each locked behind one of the major puzzles in the study. Once all three orbs are placed into the central machine, the path forward will be revealed.
How to Solve the Grandfather Clock Puzzle
The large, ornate grandfather clock on the west wall is not just for telling time; it's a sequential lock hiding the first Celestial Orb. The puzzle involves finding missing components and inputting a specific time revealed by a clue elsewhere in the room. This must be done before you can access the upper observatory.
Step 1: Find the Missing Clock Hands
Your first task is to locate the two missing clock hands. They are cleverly hidden within the study's clutter.
- The Hour Hand: Examine the large globe near the fireplace. Rotate the globe until you see a small, almost invisible seam. Use the Pocket Knife from your inventory on the seam to pry it open. The Hour Hand is tucked inside.
- The Minute Hand: Look at the bookshelf on the north wall. There is a book titled On the Passage of Time with a slightly protruding spine. Click on the spine to slide it out, revealing a hidden compartment containing the Minute Hand.
Once you have both hands, interact with the clock face. Drag the Hour Hand and the Minute Hand from your inventory onto the central pivot point of the clock to install them.
Step 2: Discover and Set the Correct Time
The clock will not open until you set it to a specific time. The clue is found by solving a preliminary light-based puzzle.
Go to the main desk and find the dusty Magnifying Glass. Pick it up. Now, observe the sunbeam filtering in from the window. Place the Magnifying Glass into the beam of light, focusing it onto the dark patch on the world map hanging on the wall. The focused light will singe the map, revealing the time 8:25 burned into the parchment.
Return to the grandfather clock. Manually drag the hands to set the time to 8:25 (the hour hand on the VIII and the minute hand on the V). A distinct click will sound, and the base of the clock will spring open, revealing the Ruby Celestial Orb.
Cracking the Alchemical Desk Sequence
The Inventor's desk is a mess of vials, burners, and locked drawers. The central drawer contains the second orb, but it's sealed by an alchemical lock that requires a specific corrosive solvent to dissolve. You must find the ingredients, decipher the formula, and mix the potion correctly.
Momento in-game screenshot
Step 1: Locate the Three Reagent Vials
Three unique reagents are needed for the formula. They are scattered around the study.
- Quicksilver Vial: This is the easiest to find. It's sitting in plain sight on a small shelf directly above the alchemical apparatus on the desk.
- Crushed Amethyst: Find the locked wooden box on the mantelpiece above the fireplace. The key is hidden under the corner of the rug closest to the desk. Use the Mantelpiece Key to open the box and retrieve the bag of Crushed Amethyst.
- Moonpetal Dew: This requires a hidden object scene. Click on the cluttered cabinet to the left of the main door to start the scene. You must find a list of 10 objects. Upon completion, you will be rewarded with the vial of Moonpetal Dew.
Step 2: Decipher the Formula and Mix the Solvent
The formula is written in the Inventor's journal, which is lying open on the desk. However, the page is covered in an invisible ink. To reveal it, light the Bunsen Burner on the desk using the Flint and Steel from your inventory. Gently warm the journal page over the flame (by dragging the journal over the burner) to reveal the instructions: "Amethyst first, then the liquid silver, and finally the calm of the moon."
Now, interact with the empty flask on the alchemical apparatus. Following the journal's instructions, add the ingredients in the correct order:
- Add the Crushed Amethyst.
- Add the Quicksilver Vial.
- Add the Moonpetal Dew.
The mixture will bubble and turn into a glowing green Corrosive Solvent. Take the flask. Use the Corrosive Solvent on the lock of the central desk drawer. The metal will hiss and dissolve, allowing you to open it and claim the Sapphire Celestial Orb.
How to Align the Star Chart Projector
The final orb is secured within the observatory, which is accessed via a ladder that descends after solving the projector puzzle. The projector is a complex device that requires three specific constellation lenses and a power source to operate.
Momento in-game screenshot
Step 1: Find the Three Constellation Lenses
The lenses are etched with celestial patterns and must be found before the projector can be activated.
- Leo Lens: This is inside a puzzle box on the small table next to the armchair. The puzzle is a simple slider game. Solve it to open the box and get the lens.
- Orion Lens: Look up at the chandelier. You'll see something glinting. Use the Extendable Grabber Tool (found next to the bookshelf) to reach up and snag the Orion Lens.
- Draco Lens: Examine the base of the large telescope. There's a loose panel. Use your Pocket Knife to unscrew it. The Draco Lens is hidden inside the compartment.
Step 2: Power the Projector and Find the Alignment Key
The projector is dead. Follow the thick cable running from its base to a floor panel. The panel is missing a handle. The handle is disguised as a decorative pull on the curtain cord next to the window. Take the Lever Handle and use it on the floor panel to open it, revealing a socket. You need to connect the Aetheric Cable, which is currently coiled up in the hidden object scene cabinet where you found the Moonpetal Dew. Go back, retrieve the cable, and plug it into the socket to power the projector.
With the power on, the device hums to life, but you need the alignment sequence. On the back of the Ruby Celestial Orb you found in the clock, there is a small inscription: Leo -> Draco -> Orion. This is the order you must use.
Step 3: Input the Final Combination
Interact with the projector's control panel. There are three slots for the lenses. Place the lenses in the slots according to the sequence you discovered: Leo Lens in the first slot, Draco Lens in the second, and Orion Lens in the third.
Pull the activation lever. The projector will cast a complex star map onto the ceiling. Three constellations will glow brightly. Click on the glowing constellations on the ceiling in the same order: Leo, then Draco, then Orion. When the correct sequence is entered, you'll hear a heavy mechanical groan from above. The ladder to the observatory will descend, and the Emerald Celestial Orb will be sitting on the bottom rung.
All Collectible Locations in Chapter 4
This chapter contains three hidden collectibles in the form of the Inventor's Schematics. Finding all of them contributes to a special achievement.
Momento in-game screenshot
| Collectible | Location |
|---|---|
| Schematic #1: Clockwork Heart | Tucked behind a loose brick in the fireplace. Click on the brick to the far right. |
| Schematic #2: Aetheric Capacitor | Inside the hollowed-out book titled Principles of Light on the bookshelf. |
| Schematic #3: Gravity Lens | Rolled up and hidden inside the leg of the tripod holding the telescope. |
Frequently Asked Questions (FAQ)
What is the time for the grandfather clock in Momento Chapter 4? The correct time for the grandfather clock is 8:25. The clue is revealed by using the magnifying glass to focus a sunbeam onto the world map on the wall.
What is the correct order for the alchemy ingredients? The correct order to mix the reagents is: 1. Crushed Amethyst, 2. Quicksilver, 3. Moonpetal Dew. This sequence is found by using the Bunsen burner to reveal invisible ink in the Inventor's journal.
Where is the Leo Lens located? The Leo Lens is inside a slider puzzle box located on the small table next to the armchair in the main study area.
How do I power on the Star Chart Projector? You must find the Lever Handle (disguised as a curtain pull), use it to open a floor panel, and then connect the Aetheric Cable (from the hidden object cabinet) to the power socket inside.
Final Steps
With all three Celestial Orbs—Ruby, Sapphire, and Emerald—in your possession, approach the large, dormant machine in the center of the room. Place each orb into its corresponding color-coded socket. The machine will whir to life, bathing the room in light and projecting a staircase of energy, concluding the chapter and opening the way to the next part of your adventure. This completes the Inventor's Study.