Question 473.e: Guns and What?

This is a newspaper article commemorating the arrival of a certain article in England.


During Napoleon's Campaign, his soldiers were accompanied by the Commission des Sciences et des Arts, a corps of 167 technical experts (savants). In mid-July 1799, as French soldiers under the command of Colonel d'Hautpoul were strengthening the defences of Fort Julien, a couple of miles north-east of the Egyptian port city of Rashid, Lieutenant Pierre-François Bouchard spotted the article that the soldiers had uncovered. He and d'Hautpoul saw at once that it might be important and informed general Jacques-François Menou, who happened to be at a place __X___.


So ID X, and what has been blanked out in the Article.
Biggest clue to the theme is given here.