This section of Call of Cthulhu guide describes the penultimate chapter 13 called Abandoned whaling station. The main protagonist gets here while searching for Sarah Hawkins and after getting through the town overrun by mad townspeople.
Get to the main room
After regaining control over your character, go towards a wooden platform and climb down the ladder, as you need a key to open the door upstairs. Ignore the mechanism that you pass - you will return here in a moment.
Upon reaching the ground, take the hook on a rope nearby. Go towards the room and go through the door to the right.
Take the Diary of the pastor's wife, volume 5 from the drawer to the right - if you collected all the previous parts, you will unlock the Detective historian achievement. Now, approach the wall with a window and examine the sheet of paper lying on the floor - Page torn from log I. Leave the room, go a bit right, and enter the next one.
Approach the right side of the desk and take the office key from the top drawer. Turn around by 180 degrees and examine Page torn from log 2 on the damaged bookcase.
Leave the room and climb the ladder. Go to the end of the gangplank and use the key to get inside the room. Approach the counter and take the knife. Next, approach the window from the right and examine Page torn from log 4. Finally, approach the valve from the left and turn it.
The mechanism hanging above the floor will make the tank on the chain move left. Leave through the door to the left, approach the tank, and install the newly-acquired hook on a line on it. Return to the room with the valve and turn it again. Now, go to the line you've just installed and cut it using the knife to activate a cutscene.
Find Sarah Hawkins
Go downstairs and through the newly opened passage. Go to the lower level and approach Sarah, to activate the cutscene. Approach the desk and pick up the phone. After regaining control over your character, go to the door and go through it to return to the previous location.
Before you continue, return to the room. Investigate the photos on the table and the note from the middle desk drawer, in which you will find Page torn from log 3.
Finally, approach the crate in the corner and open it using the main protagonist's ability. After you do so, you will unlock the Voyage into history hidden achievement. Before you leave the room, take the book that increases Medicine (Excision of the Madness Stone) from the file cabinet nearby.
Now, leave the room and take the only available way to reach a hatch in the floor. Open it and jump inside. Go to the other end of the pipes. Leave this path and run towards Sarah to activate another cutscene.
After you get to the cell, you will start talking to Dr. Fuller. Then, turn around and go to the medicine vial - you can decide whether to take it or not (the description of the consequences can be found in the chapter titled "The endings in Call of Cthulhu"). Now continue to the next part of the room and decide whether you want to eat Leviathan's meat. After getting into one room with Dr. Fuller approach the weapon to the right and decide whether to use it or not.
After you return to the previous location, approach Sarah to switch locations once again. Here, you have to go through several doors until you get to an open room with a few puzzles to solve.
First, go through the passage to the right until you reach the fork. Go on the penultimate gangplank, turn right, left, and then left again to get to the hardpan.
Now stand in front of the valves and turn the one to the left. Return to the beginning of this location and go through the passage to the left.
You will reach four sets of valves. When standing in front of them, turn the front one from the second right set. After doing so, return to the start of this location and pull the lever by the furnace.
After regaining control over your character, you have to run, as everything is starting to collapse. This does not differ much from the previous escape sequence - run ahead and do not stop, as there is nothing interesting to collect. At the end of your route, a cutscene ending this chapter will activate.