© Bodleian Library
Map of Zeppelin routes tracked by Marconi Direction Finding equipment on 27-28 November 1916. Zeppelins (German airships) were used for reconnaissance and for bombing raids over the east coast of Britain. H.J. Round, working for military intelligence, developed a method of locating and tracking the source of wireless signals emitted by ships or airships, thus being able to follow the routes of vessels so equipped. This technique - known as direction finding - was used to detect the paths of Zeppelins in several instances. This map shows one such occurrence; two airships were shot down at the places marked.
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