Notations Cora Boone wrote on the old mat read: "From the deck of our steamer as we were nearing the British Isles / It was a lovely sunset / "Sunset" at Sea (from the Deck as we headed into Ireland for a stop / Rough "Sugar paper" (Lift it & see the color) / Needs a narrow bright gold frame & a cream mat / Sunset at Sea / Copy by CB / (See Reverso side-I must "work-up" the Venice sketch on back)".
The "Venice sketch" she is referring to can be seen in the second image.