L'art pompier, literally "Fireman Art", is a derisory late nineteenth century French term for large "official" academic art paintings of the time, especially historical or allegorical ones. It derives from the fancy helmets, with horse-hair tails, worn by French firemen - now only for parades - which are fatally similar to the Greek-style helmets often worn in such works by allegorical personifications, classical warriors, or Napoleonic cavalry. Pompier art was seen by those who used the term as the epitome of the values of the bourgeoisie, and as insincere and overblown.

pompier (1888). Fam. Se dit d'un artiste (ou de ses oeuvres) qui traite des sujets académiques dans un style prétentieux
[Larousse Lexis, where it is under "pompe" = "déploiement de faste (firemen are fast!!!), de luxe ..."

There's even "pompiérisme", Fam. Prédilection pour le style pompier.

Although based on "pomp (and circumstance)", I can well imagine that as a "familier" coinage, it was intended to be confused with "pompier", the fireman, with a broad moustache, muscles (no motor-driven pumps in them days!), a swagger, and a way with girls ... a show-off.

Grist to the mill. Still working on a translation ...

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Note added at 2 hrs (2007-08-17 13:41:07 GMT)
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Pompous academic art. Or in your sentence, "a concentrate of academic art at its worst", "a sort of concentrate of academic art, supposedly a bourgeois painter, the sort producing ludicrously pompous works", or anything with "ludicrous pomposity". Along those lines (don't go over, don't smudge, and put the right colours on the right numbers).

ACADEMIC ART is a style of painting and sculpture produced under the influence of European academies or universities.
Specifically, academic art is the art and artists influenced by the standards of the French Académie des beaux-arts, which practiced under the movements of Neoclassicism and Romanticism, and the art that followed these two movements in the attempt to synthesize both of their styles, and which is best reflected by the paintings of William-Adolphe Bouguereau, Suzor-Coté, Thomas Couture, and Hans Makart. In this context it is often called "academism", "academicism", "L'ART POMPIER", and "eclecticism", and sometimes linked with "historicism" and "syncretism".
[...]
The French referred DERISIVELY to the style of ACADEMIC ART AS L'ART POMPIER (pompier means fireman) alluding to the paintings of Jacques-Louis David (who was held in esteem by the academy) which often depicted soldiers wearing fireman-like helmets [I suspect this is a simplification, or said in ignorance, since there is no mention of the word "pompe"]. The paintings were called "grande machines" which were said to have manufactured false emotion through contrivances and tricks. http://en.wikipedia.org/wiki/Academic_art

When I was studying in art school, there was bad painting and good painting. So I heard and learned a lot about Courbet, Matisse, Van Gogh, Cézanne and Picasso… But no teacher talked to me about Bouguereau or Gérôme. Their art was called "ACADEMIC" OR "ART POMPIER" (in french). It was historical painting, with mythological scenes and great battles. It was the official art in the French Second Empire. For a complete review, see wikipedia
http://muttpop.blogspot.com/2006_10_22_archive.html

HOGARTH's naturalism goes hand-in-hand with a dislike for ACADEMIC ART and for all things foreign. Elegant without being POMPOUS, he will start a subject ...
news.surfwax.com/art/files/Academic_Art_Art.html

See also Academic art, Napoleon III of France, Second Empire. The expression POMPIER IS PEJORATIVE and means POMPOUS ; it refers to Academic painters in the ...
en.wikipedia.org/wiki/List_of_French_artistic_movements

His [Sir Joshua Reynolds'] works can be divided into two types. The first is where he struggled to “elevate” the genre of portraiture with the help of classic samples and associations. Such compositions are POMPOUS and contain allegoric figures and details, taken from classical mythology and art. The models in these works are idealized and very often the subjects are Greek and Roman deities
http://www.abcgallery.com/R/reynolds/reynoldsbio.html

They were POMPOUS, self-important, and extremely poorly painted ..... as the best academic art is recondite, polite, and inscrutably arcane. ...
www.jameselkins.com/Texts/failureacademic.pdf

The question is, do you want to translate the meaning of "pompier" for readers who don't know it, or is your text directed at a sophisticated reader who will appreciate the precise connotations of the term? (You wouldn't replace "rococo" or "baroque" with explanatory synonyms!)