The legs probably came from a sitting statue like this: https://english-303-final.wikispaces.com/Historical+Content+%26+Historical+Context+in+Ozymandias https:

The legs probably came from a sitting statue like this: https://english-303-final.wikispaces.com/Historical+Content+%26+Historical+Context+in+Ozymandias https://english-303-final.wikispaces.com/Historical+Content+... While it is true that Shelley was motivated to write the poem by the imminent arrival in London of the Younger Memnon statue, the scene that the poem describes is not consistent with that particular statue (which consists of an upper torso) rather than a separate head and trunkless legs located in its original desert setting.