21.   On other fronts, including video, photography and installation art, the season brought strong first and second shows by several artists.

22.   On one recent afternoon here, hundreds of shoppers mulled over abstract paintings, installation art and African masks as they strolled from gallery to gallery.

23.   Such physical limitations are among the hidden costs of investing in installation art.

24.   The fascination with natural history dioramas among young artists today is not necessarily just another ironic extension of the catch-all category of installation art.

25.   The fact that installation art is pegged as a Western form also raises difficulties.

26.   The gallery owner Paula Cooper, who represents Gober and has championed installation art for decades, can count the number of serious collectors in a single breath.

27.   Think of them as installation art under glass.

28.   This is pretty much the essential operating principle of installation art.

29.   When installation art fails, and too frequently it does, it naturally seems to incline that way.

30.   With more installation art on display, it was only a matter of time before wealthy collectors would covet the work, no matter how unwieldy.