Instructions on how to rotate the tower in Myst library and get the access key to unlock the spaceship.
Rotate the Tower
In the library on Myst Island, go to the portrait of the island and click and hold the blinking circle to rotate the tower so that the red line stops on the spaceship. Then click the portrait in the library that shows a staircase, to turn the bookshelf into a staircase. Go up, then go to the end of the hallway and take the elevator up to the tower. Go up the ladder with the key plaque behind it. The access key for the spaceship is:
Open the Spaceship
Go back to down to the main library room, and click the portrait of the open door to reopen the library door. Go outside and go straight. Go past the fountain with the ship in it, then go into the brick building on the right.
Go down the stairs and go to the end of the path, and push the button next to the metal door to open it. In the room ahead, there are ten buttons, with two meters to the left. Each button adds a specific number of volts to the current output. The meter on the left shows how many volts are being generated, and the meter on the right shows how many volts the spaceship is receiving.
Be warned that if you exceed 59 volts, you will trip the circuit breakers to the spaceship, and the meter on the right will go to 0. If this happens, you need to go outside, turn to face the brick building that you just came out of, and go to the right, where there is a brick tower. Go to the tower, and climb up the ladder, and flip the switch at the top. There is a second tower that you can find by going toward the spaceship, and instead of following the path to the spaceship, go to the brick tower that you can see nearby, and climb the ladder and flip the switch there. This will reset the two circuit breakers, allowing you to try using the generators again.
The buttons create this much output:
10 01 07 02 08 22 16 19 05 09
There are several different ways to get 59 volts. Here is one example:
When you get both meters to say 59, go to the spaceship and check on the door to open it. Inside, you will see a device against one wall, and a pipe organ against the other. The device has five sliders, and sliding them up and down will play musical notes. The clue for this puzzle is
After making a note of the diagram, go back to the spaceship and play the notes in order on the pipe organ. Then turn around and slide the sliders so that each note matches the song that you played, going from left to right. Then pull the lever, and a linking book will appear in the display above. Click it to go to the Selenitic Age.