Tipu had a larger army than this – more than 50,000 sepoys and cavalry troopers – but he was too careful a general to risk open battle against such a formidable force. Instead he stayed within the magnificent fortifications of Srirangapatnam which had been designed for him by French engineers on the latest scientific principles, following Sébastian de Vauban’s research into artillery-resistant fortification designs, as adapted by the Marquis de Montalembert in his book La Fortification Perpendiculaire.