>>5734249wow, I am in awe of your memory, I did just look it up in the appendices and glossary, you are absolutely correct! I forgot this detail hehe
The other day I was reading about landmines,
https://www.ft.com/content/bbff1949-4f06-43ad-9691-7c124edbd004the Soviet butterfly mine PF-1 named because it is air-dropped and descends whilst self-arming on two spin-stabilised propeller wings (it is a pressure primer, cannot be disarmed) It turns out this butterfly mine was a Soviet clone of the US Dragontooth during Vietnam, the classified operation IGLOO WHITE in Laos to interdict the Ho Chi Minh trail etc. Anyway, it turns out that part of this operation involved minefields interlaced with extensive electronic reconaissance, air delivered seismic sensors based upon underground mapping for the oil industry ADSID, air delivered seismic intrusion detector.
When I read this, I immediately thought about the thumpers in Dune! The novel came out in 1965 this operation was I think 1968 but I just thought it was strange how some of this technology which appears bizarre or farcical in the fiction, but makes sense if you situate it in historical context. If you think of the Fremen weird sand-walking (no matter the calibre of acting ability, this always remains cringe-inducing in both Dune 1984 and 2021) think of the sandwalking and the thumpers as an analogy for crossing a minefield, it suddenly makes a lot more sense...