The second angel poured out its vessel on the sea, and there came blood as it were of a dead man; and every living soul died in the sea.(Apocalypse 16:3)
Gesturing toward its overturned vessel, from which the second of the final seven plagues has just been released, the angel turns to Saint John. Blood pours forth, represented in the miniature as a great red swath cutting through the water. The bodies of the stricken are visible through the transparent sea.