page_title: Trunnion
section_title: Initial significance
hierarchical_section_title: Trunnion / Initial significance
caption_attribution_description: Español: Muñón derecho
context_page_description: A trunnion is a cylindrical protrusion used as a mounting or pivoting point. First associated with cannons, they are an important military development.
  Alternatively, a trunnion is a shaft that positions and supports a tilting plate. This is a misnomer, as in reality it is a cradle for the true trunnion.
  In mechanical engineering, it is one part of a rotating joint where a shaft is inserted into a full or partial cylinder.
context_section_description: Due to its capabilities, the French- and Burgundy-designed siege gun, equipped with its trunnions, required little significant modification from around 1465 to the 1840s.
  King Charles VIII and the French army used this new gun in the 1494 invasion of Italy.  Although deemed masters of war and artillery at that time, Italians had not anticipated the innovations in French siege weaponry. Prior to this, field artillery guns were huge, large-caliber bombards: superguns that, along with enormous stones or other projectiles, were dragged from destination to destination. These behemoths could only be used effectively in sieges, and more often than not provided just a psychological effect on the battlefield; owning these giant mortars did not guarantee any army a victory. The French saw the limitations of these massive weapons and focused their efforts on improving their smaller and lighter guns, which used smaller, more manageable projectiles combined with larger amounts of gunpowder. Equipping them with trunnions was key for two reasons: teams of horses could now move these cannons fast enough to keep up with their armies, without having to stop and dismount them from their carriages to achieve the proper range before firing. Francesco Guicciardini, an Italian historian and statesman, sometimes referred to as the “Father of History,” wrote that the cannons were placed against town walls so quickly, spaced together so closely and shot so rapidly and with such force that the time for a significant amount of damage to be inflicted went from a matter of days (as with bombards) to a matter of hours. For the first time in history, as seen in the 1512 battle of Ravenna and the 1515 Battle of Marignano, artillery weaponry played a very decisive part in the victory of the invading army over the city under siege. Cities that had proudly withstood sieges for up to seven years fell swiftly with the advent of these new weapons.
  Defensive tactics and fortifications had to be altered since these new weapons could be transported so speedily and aimed with much more accuracy at strategic locations. Two significant changes were the additions of a ditch and low, sloping ramparts of packed earth that would surround the city and absorb the impact of the cannonballs (glacis), and the replacement of round watchtowers with angular bastions. These towers would be deemed trace Italienne.
  Whoever could afford these new weapons had the tactical advantage over their neighbors and smaller sovereignties, which could not incorporate them into their army. Smaller states, such as the principalities of Italy, began to conglomerate. Preexisting stronger entities, such as France or the Habsburg emperors, were able to expand their territories and maintain tighter control over the land they already occupied. With the potential threat of their land and castles being seized, the nobility began to pay their taxes and more closely follow their ruler’s mandates. With siege guns mounted on trunnions, stronger and larger states were formed, but because of this, struggles between neighboring governments with consolidated power began to ensue and would continue to plague Europe for the next few centuries.
caption: Gun trunnions often bear factory markings
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