He was still a student at the Roman Jesuit College when, in 1729, Raimondo di Sangro made his remarkable debut as an inventor. Having to build, in the courtyard of the College, a stage which would disappear after a theatrical performance to make room for an equestrian display, and after the plans presented by the best engineers in Rome had been examined, the young Prince’s design was chosen, which envisaged the raising and closing of the stage in a very short time.
The machinery – di Sangro recalls – was made up of “winches and wheels unseen by the spectators”. So, “with the help of a few ropes”, the stage withdrew “in a few moments” resting on the façade of the courtyard, which was now completely empty. It was no less than Nicola Michetti, the already famous Engineer of Czar Peter the Great, who preferred the mechanism thought up by the Prince over all the others. The press report of the evening at the Collegio Romano, entitled Votes for the Succession of the Most August House of Austria, also bears witness to the perfect functioning of the “fine mechanical invention”.
According to a short biography dating from the early nineteenth century, di Sangro is said later to have told his intimate friends and his daughter Carlotta that the plan for the stage “had been suggested to him in a dream by a venerable old man calling himself Archimedes”. Whether the dream apparition was real or not, it is plausible that the Prince wanted to show that the brilliant scientist from Syracuse was his model, almost the ideal initiator of his long and varied experiments.