Oddly neither the title nor the blurb on the back of the book is entirely accurate. The book covers more than just heavy artillery, also including light and medium artillery, mortars and anti-tank guns. The blurb claims that air defence weapons, railway guns and rocket launchers are included, but the author's introduction makes it clear that they have been excluded due to lack of space and will be in a separate volume (already available in German). A second minor flaw is that the glossary hasn't been translated from German.
Each weapon gets a brief history of its development, a technical description and production details. This is supported by a table of technical specifications and at least one photo. In a few cases pictures of the weapon haven't been found and drawings have been used instead, mainly taken from contemporary US intelligence reports.
The book covers German designed weapons, captured weapons taken into service, and weapons produced for the Germans in occupied areas, in particular by the Skoda Works, which emerges as nearly as important as Krupp and Rheinmetall. Some captured types were also important - I didn't realise how many British 25-pounders were used by the Germans, in some cases equipping entire batteries.
This sort of book is always good for turning up interesting snippets. I hadn't realised that the '18' used at the end of many older German weapons of the Second World War was used to hide weapons developed in the early 1930s by making it look as if they were left over from the period before the Treaty of Versailles.
This book has two advantages over more general weapons guides. First is the inclusion of a wide variety of German guns, including the more important developmental models. Second is the examination of foreign-made guns from the German point of view, rather than having that as a footnote to their original use. The author is also good on the connections between different guns, treating them as related rather than as isolated items.
Overall this is a useful guide to the topic - too detailed to be called an overview.
Light Field Guns
Medium Field Guns
Heavy Field Guns
Author: German Heavy Artillery Guns 1933-1945, Alexander Lüdeke
Publisher: Pen & Sword Military