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The Prussian army was controlled by the General Staff, under Field Marshal Helmuth von Moltke. The Prussian army was unique in Europe for having the only such organisation in existence, whose purpose in peacetime was to prepare the overall war strategy, and in wartime to direct operational movement and organise logistics and communications. The officers of the General Staff were hand-picked from the Prussian Kriegsakademie (War Academy). Moltke embraced new technology, particularly the railroad and telegraph, to coordinate and accelerate mobilisation of large forces.

Who commanded the General Staff?
Answer: Field Marshal Helmuth von Moltke
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Initially sensors were optical and acoustic devices developed during the First World War and continued into the 1930s, but were quickly superseded by radar, which in turn was supplemented by optronics in the 1980s. Command and control remained primitive until the late 1930s, when Britain created an integrated system for ADGB that linked the ground-based air defence of the army's AA Command, although field-deployed air defence relied on less sophisticated arrangements. NATO later called these arrangements an "air defence ground environment", defined as "the network of ground radar sites and command and control centres within a specific theatre of operations which are used for the tactical control of air defence operations".

When were sensors initially developed?
Answer: during the First World War
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Bitumen was used in early photographic technology. In 1826 or 1827, it was used by French scientist Joseph Nicéphore Niépce to make the oldest surviving photograph from nature. The bitumen was thinly coated onto a pewter plate which was then exposed in a camera. Exposure to light hardened the bitumen and made it insoluble, so that when it was subsequently rinsed with a solvent only the sufficiently light-struck areas remained. Many hours of exposure in the camera were required, making bitumen impractical for ordinary photography, but from the 1850s to the 1920s it was in common use as a photoresist in the production of printing plates for various photomechanical printing processes.[not in citation given]

What feature of bitumen use in photography made it impractical?
Answer:
hours of exposure