Cropped from a photo in the Album of Hongkong Canton Macao Amoy Foochow : vol.1 / 33.
This is very likely HMS Melville which was used as a hospital ship from 1857-1873. She was a 74-gun third rate ship of the line. This type had two gun decks which can seen on the photo, also the (closed) gun ports.
Date picture taken
1870 (year is approximate)
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