Il disegno delle fortezze viste dagli assedianti

Speaking of the fortresses is normally referred to as drawings made by military engineers to build or modify the defensive works. These are the most popular designs and the most studied, being made at the table using all the means available graphics to make them appealing to the eye, immediately understandable and metrically ‘perfect’. However, there are drawings of fortresses built by those who have to besiege and conquer them where point of view is diametrically opposed although the subject represented is practically the same. They are quickly made on the field, with makeshift graphic tools and in dangerous conditions because very often the result of dangerous and uncertain espionage. They are not drawings derived from trigonometric operations but the result of detection of a relief in view of what is visible in perspective from a point of view which often is located at a height not much higher than the relief of the object. They are not considered as less useful to historians of Architecture and Urban, seeking documentary evidence on the state of things in a certain period. The graphic quality and accuracy of these designs is not remotely comparable to that of the first category, and yet they represent a very important documentary evidence for the history of the representation and give us information not about the art of military defences, but on the siege. Without saying that on some fortifications lost and undocumented through representations of detectors and designers, the designs of the besiegers and spies constitute the only available graphic testimony. To describe this type of representations will be taken of drawings related to the military campaigns in Sicily of 1718/1720 and 1735.