It was common for artists, while working for patrons interested in studying, measuring and recording ancient monuments, to include little portraits of themselves at work. Here, while Préaulx sketches in the foreground, accompanied by two curious Turkish onlookers, his patron or patrons are examining the Goth’s Column, a granite monolith 15 metres high, surmounted by a Corinthian capital. In the background is the wall and gateways to the palace grounds. This column, (probably recycled from a temple) is alleged to date from the time of Constantine the Great, perhaps just after 332. It is one of the oldest but least known monuments in Istanbul and commemorates a victory over the Goths, as its partly visible inscription states. It stands in what is now Gülhane Park, amongst the trees, next to a tea garden and a zoo, between the palace of Topkapi and Saray Burnu (Seraglio Point).

Almost nothing is known about Préaulx’s early life, except that he possibly studied in Rome. He arrived in Istanbul in 1796, with a group of fellow French architects, engineers, cannon founders and artists, commissioned to supply military and naval installations for the Ottoman forces. The French had been invited by Sultan Selim III, desperate to improve the defences of his empire, threatened by hostile nations, especially Russia, and by internal rebellions. Somehow Préaulx survived the difficulty of Napoleon’s France subsequently changing from an ally to an enemy of the Ottomans, and he continued to execute topographical drawings for many British and French visitors, including Lord Elgin, British Ambassador in Istanbul, 1799-1803.