I noticed a recurring motif during ’12 Years a Slave’.
It begins with the scarring on Solomon Northup’s back after his lashing.
The Keloid scarring forms repetitive bumps/ridges on his back.
On the slave ship, he throws a dead body over the side and into the water.
The wake left by the boat forms waves which have the bumps/ridges repetitive motif.
In this image below, his scarring is covered by his clothing, but the cross-lacing on the back of his shirt repeats the bump motif
This scene below begins with his back to the ranch steps, which cascade down to his back, again in the ridged, bump formation
When invited to sit at the table for refreshment, the conversation begins with house shutters behind him, which have a ridged surface
Solomon again is framed by a staircase cascading down to where he lays on the floor.
In this scene, he has his back turned to the wall which he is building. The wood form the waves and ridges that can represent his scarring on his back
And of note, in his conversation with Pitt, who agrees to write correspondence to his friends in the north, that could potentially help in his freedom. Pitt asks him to hand the wood shavings which were piled up behind Solomon during the conversation. The shavings are stacked in a way which form ridges.
– Rhett Bartlett