Falconry training and technique two part restraint featuring an anklet that is grommeted on, and a removable jess strap. Some Aylmeri jess straps have dental rubber bands on them to make it more difficult for the bird to pull out the jess, but they are still removable if the bird gets caught up outdoors. The third type of jesses is a combination of the two, referred to as "false Aylmeri." These use an anklet as well, but a brass eyelet is slipped through, far enough away that the toes will not get caught in it. There are two straps attached to the anklet, flying
Leather cannon especially if the terrain was uneven. Gustavus Adolphus' tactics were based on use of effective firepower. While heavy cannon were effective at the start of the battle, they could not be moved from the hill that they usually were deployed on (the guns themselves weighed from roughly 300 kilograms (660 pounds) to 3 tons). As such, the artillery could not respond effectively to developments in battle. In order to fill the gap, the so-called "leather cannon" was developed. A relatively thin copper tube was reinforced by heavy cords and finally clad in leather (alternatively clad in leather straps first and