May mean any kind of gun dragged out of the fortresses (inside Germany and captured ones in Belgium, France or Russia), generally with calibres between 3.7 cm and 7.7 cm firing grapeshot. This includes the 5.3 cm guns in Fahrpanzer, which had been designed for repulsing night attacks.
Acc to Herbert Jäger the Grabenkanone was a makeshift Krupp design using the tubes of the old Gruson 3.7cm revolving guns "retired from the fortifications to the depots by the machine gun." It was, apparently, different from the 3.7cm Sturmbegleitkanone, although both came from the same origins.
Will post more details if you wish.
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"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
I believe that the first original of that gun , with the name "Grabenkanone" was that gun.....one of the first modells with brass cartridge (case).That`s 37mm Krupp gun from 1892(pic is from the export catalogue of Fried. Krupp Essen-Rheinpreussen-1892)
Thanks for posts memo but you may wish/need to know that your image host, prikachi.com, is barring access from my connection (Requesting the server's default page. The server returned the following response headers: HTTP/1.1 403 Forbidden). No problem if I am the only one (IP address 124.169.xxx.xxx - IINET-AU - whois.apnic.net) but if you have any influence with that host they should be required to justify exclusions. Well, MY exclusion anyway.
Not the only one - my Telstra Bigpond connection 124.189.206.*** is also blocked. It probably would be better to download and attach images rather than link them - many image hosting sites don't permit remote linking.
