Editing Fish (cryptography) (section)

===Sturgeon===
This was the name given to traffic encoded with the [[Siemens and Halske T52]] ''Geheimschreiber''.<ref>{{ Harvnb | Weierud | 2006 | pp=307–327 }}</ref><ref>{{ Harvnb | Smith | 2006 | p = 35 }}</ref> In May 1940, after the German invasion of Norway, the Swedish [[mathematician]] and [[cryptographer]] [[Arne Beurling]] used traffic intercepted from telegraph lines that passed through Sweden to break this cipher.<ref>{{ Harvnb | McKay | 2006 | pp = 328–333 }}</ref>  Although Bletchley Park eventually diagnosed and broke Sturgeon, the relatively low value of the intelligence gained, compared to the effort involved, meant that they did not read much of its traffic.