Topic: Military history/World War I
Pigeon photography is an aerial photography technique invented in 1907 by the German apothecary Julius Neubronner, who also used pigeons to deliver medications. A homing pigeon was fitted with an aluminium breast harness to which a lightweight time-delayed miniature camera could be attached. Neubronner's German patent application was initially rejected, but was granted in December 1908 after he produced authenticated photographs taken by his pigeons. He publicized the technique at the 1909 Dresden International Photographic Exhibition, and sold some images as postcards at the Frankfurt International Aviation Exhibition and at the 1910 and 1911 Paris Air Shows.
Initially, the military potential of pigeon photography for aerial reconnaissance appeared interesting. Battlefield tests in World War I provided encouraging results, but the ancillary technology of mobile dovecotes for messenger pigeons had the greatest impact. Owing to the rapid perfection of aviation during the war, military interest in pigeon photography faded and Neubronner abandoned his experiments. The idea was briefly resurrected in the 1930s by a Swiss clockmaker, and reportedly also by the German and French militaries. Although war pigeons were deployed extensively during World War II, it is unclear to what extent, if any, birds were involved in aerial reconnaissance. The United States Central Intelligence Agency (CIA) later developed a battery-powered camera designed for espionage pigeon photography; details of its use remain classified.
The construction of sufficiently small and light cameras with a timer mechanism, and the training and handling of the birds to carry the necessary loads, presented major challenges, as did the limited control over the pigeons' position, orientation and speed when the photographs were being taken. In 2004, the British Broadcasting Corporation (BBC) used miniature television cameras attached to falcons and goshawks to obtain live footage, and today some researchers, enthusiasts and artists similarly deploy crittercams with various species of animals.
- "Pigeon photography" | 2014-07-17 | 79 Upvotes 11 Comments
A synchronization gear, or a gun synchronizer, sometimes rather less accurately called an interrupter, is attached to the armament of a single-engine tractor-configuration aircraft so it can fire through the arc of its spinning propeller without bullets striking the blades. The idea presupposes a fixed armament directed by aiming the aircraft in which it is fitted at the target, rather than aiming the gun independently.
There are many practical problems, mostly arising from the inherently imprecise nature of an automatic gun's firing, the great (and varying) velocity of the blades of a spinning propeller, and the very high speed at which any gear synchronizing the two has to operate.
Design and experimentation with gun synchronization had been underway in France and Germany in 1913–1914, following the ideas of August Euler, who seems to have been the first to suggest mounting a fixed armament firing in the direction of flight (in 1910). However, the first practical—if far from reliable—gear to enter operational service was that fitted to the Eindecker monoplane fighters, which entered squadron service with the German Air Service in mid-1915. The success of the Eindecker led to numerous gun synchronization devices, culminating in the reasonably reliable hydraulic British Constantinesco gear of 1917. By the end of the war German engineers were well on the way to perfecting a gear using an electrical rather than a mechanical or hydraulic link between the engine and the gun, with the gun being triggered by a solenoid rather than by a mechanical "trigger motor".
From 1918 to the mid-1930s the standard armament for a fighter aircraft remained two synchronized rifle-calibre machine guns, firing forward through the arc of the propeller. During the late 1930s, however, the main role of the fighter was increasingly seen as the destruction of large, all-metal bombers, for which the "traditional" light armament was inadequate.
Since it was impractical to try to fit more than one or two extra guns in the limited space available in the front of a single-engine aircraft's fuselage, this led to an increasing proportion of the armament being mounted in the wings, firing outside the arc of the propeller. There were in fact some advantages in dispensing with centrally mounted guns altogether. Nevertheless, the conclusive redundancy of synchronization gears did not finally come until the introduction of jet propulsion and the absence of a propeller for guns to be synchronized with.
- "Synchronization gear" | 2020-01-19 | 54 Upvotes 15 Comments
The Wire of Death (Dutch: Dodendraad, German: Todesdraht) was a lethal electric fence created by the German military to control the Dutch–Belgian frontier during the occupation of Belgium during the First World War.
- "Wire of Death" | 2016-04-09 | 158 Upvotes 75 Comments
The Black Tom explosion was an act of sabotage by German agents to destroy U.S.-made munitions that were to be supplied to the Allies in World War I. The explosions, which occurred on July 30, 1916, in the New York Harbor, killed four people and destroyed some $20,000,000 worth of military goods. This incident, which happened prior to U.S. entry into World War I, also damaged the Statue of Liberty. It was one of the largest artificial non-nuclear explosions to have ever occurred.
- "Black Tom Explosion" | 2020-09-22 | 60 Upvotes 49 Comments
The Boirault machine (French: Appareil Boirault), was an early French experimental landship, designed in 1914 and built in early 1915. It has been considered as "another interesting ancestor of the tank", and described as a "rhomboid-shaped skeleton tank without armour, with single overhead track". Ultimately, the machine was deemed impractical and was nicknamed Diplodocus militaris. It preceded the design and development of the English Little Willie tank by six months.
- "Boirault Machine" | 2021-04-25 | 40 Upvotes 3 Comments