Click on the desk at the right side of the room to see this little puzzle. Read to the end of this hint for the answer.
Hint 2
To open the desk, you need to fill in the three blank squares in the center, putting in the right number and the right color. To change a square's color or number, click on the square, then click on the number or color at the right.
Hint 3
This is a matter of seeing patterns -- that is, look at the completed rows and see what the numbers in those rows seem to be doing. (You can ignore the columns.)
Hint 4
The numbers aren't in a progression; the pattern would be the same if you mixed them up. Does that help?
Hint 5
Add up all the numbers in a completed row and see what you get.
Hint 6
The numbers in each row add up to 9. So the missing numbers should do the same in their rows.
Hint 7
As for the color, that's a little less clear. What seems to work is making the colors a mirror -- that is, the left side should look exactly like the right.
Hint 8
From left to right, the empty squares should be --
Hint 9
-- 1 yellow, 3 yellow, 1 red.
Hint 10
Inside the desk, you'll find the key to the lighthouse, a newspaper article with an angry note from Dagny, and Magnus's journal. You can't take the journal with you, so take pictures of any parts you want to remember (especially the last page).