Answer:
Delacoix and Gericault both used an lighting and colours in a unique way. Their work also comprised of Allegories.
An allegory is a picture that can needs to be decoded to unveil a secret or hidden moral and or political idea or information.
In this case, it was a topless woman holding a firearm fitted with a bayonet. The painting was such that the lighting effect focused much more on the woman. She was depicted to be leading the army whilst parading a three-coloured flag (red, white and blue). She was also putting on a Phrygian cap. The Phrygian cap is similar to that given to newly freed slaves - a symbol of freedom.
In the Raft of Medusa on the other hand, the lighting effect was used to accentuate the dead bodies or those were weak and dying. The raft had sailed off with 150 people on board, only about 13 survived.
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