On this page of the Call of the Sea guide, you will find the location of all the secrets in Chapter 3 - The Vanishing of the lady Shannon.
Chapter 3 - The Vanishing Of Lady Shannon.
Location: in the first part of the camp.
To get to this room, you have to turn on the power.
Description of the solution to this puzzle can be found on the page: current.
The Can is in the chest, in the first tent on the left.
At this point, you can get an achievement!
When you examine the can you get the achievement - Marsh Cannery.