during the Siege of Ladysmith. On October 5, 1907, Colonel John Capper (late Royal Engineers) and team flew the military airship Nulli Secundus from Farnborough around St. Paul's Cathedral in London and back with a view to raising public interest. World War I World War I was the high point for the military use of observation balloons, which were extensively deployed by both sides. The British, despite their experience in late 1800s Africa, were behind developments and were still using spherical balloons. These were quickly replaced by versions, commonly referred to as kite balloons, which were flyable and could operate in more extreme weather conditions; at first the German Parseval-Siegsfeld type balloon, and then French Caquot type dirigible. By World War I, artillery had developed to the point where it was capable of engaging targets beyond the visual range of a ground-based observer. Positioning artillery observers on balloons, generally a few miles behind the front lines and at altitude, allowed them to see targets at greater range than they could on the ground. This allowed the artillery to take advantage of its increased range. Because of their importance as observation platforms, balloons were defended by anti-aircraft guns, groups of machine guns for low altitude defence, and patrolling fighter aircraft. Attacking a balloon was a risky venture but some pilots relished the challenge. The most successful were known as balloon busters, including such notables as Belgium's Willy Coppens, Germany's Friedrich Ritter von Röth, America's Frank Luke, and the Frenchmen Léon Bourjade, Michel Coiffard and Maurice Boyau. Many expert balloon busters were careful not to go below in order to avoid exposure to anti-aircraft guns and machine-guns. World War I observation crews were the first to use parachutes, long before they were adopted by fixed wing aircrews. These were a primitive type, where the main part was in a bag suspended from the balloon, with the pilot only wearing a simple body harness around his waist, with lines from the harness attached to the main parachute in the bag. When the balloonist jumped, the main part of the parachute was pulled from the bag, with the shroud lines first, followed by the main canopy. This type of parachute was first adopted by the Germans and then later by the British and French for their observation balloon crews. Observation balloons began to be used at sea for anti-submarine purposes towards the end of