This may be a stretch but one of the paintings of Hieronymous Bosch is called the Circle of Hell which contains an assortment of odd creatures. As a central image there is a wheel coming out of (or going into) the mouth of a fishlike creature. The reference to hell seems appropriate for Telluride and a Japanese trade delegation in a Colorado bar may suggest the odd creatures. Just to stretch the connection a bit further, there was another Bosch, Robert, a Germany engineer who perfected a magneto ignition device in 1897 that became the standard for creating electrical sparks to start internal combustion engines. The modern Bosch Group is a leading manufacturer of automotive and industrial technology.
- While there is most certainly something Boschean about Pynchon's aesthetic, nothing in the context of this passage suggests an association with either the painting described above or the machinist Robert Bosch. Instead, the passage indicates that the term describes a roulette wheel. Neither Google nor the OED recognize the term in any meaningful way, though it may be a back formation from the term "jerry," meaning to tumble, Hieronymous being the latinate form of Jerome. This etymology is still a considerable stretch, but it fits the passage better. For an example of an AtD passage that does conjure Old Master depictions of Hell (of which Bosch painted several), albeit without suggesting Bosch specifically, see p. 210-11, "the first glimpse of Jeshimon . . . . advanced the hour."
Although this is the sort of discussion that should be held on the "Discussion" page, apparently we're arguing here. As much as I despise frivolous interpretations, I must agree with the original post. The text does describe a roulette wheel, but there exist much more direct forms of doing so. The passage would make sense without the wheel being described as "Hieronymus", but that epithet persists. It cannot be accidental.
--- I believe Pynchon is alluding to the drinks counter, and to the similarity of it to a Bosch painting, hellish or however one'd like to interpret it. Also,c.f. Bosch's Seven Deadly Sins:
http://www.ibiblio.org/wm/paint/auth/bosch/7sins/7sins.jpg Nmaranca 09:10, 27 January 2008 (PST)