Below is the beginning of the review:

LONDON — At first blush “Close Examination: Fakes, Mistakes and Discoveries,” here at the National Gallery, has the quaint, cheerfully scholastic earnestness of a science fair. Some 30 pictures from the permanent collection, most of them culled from storage, have been enlisted to anchor a flurry of wall texts, X-rays and the sort of enlarged microscopic cross sections of layered pigments and varnish vaguely resembling the cautionary photographs of plaque that elementary school teachers flourish before floss-wary fourth grader

A celebratory primer on polarized light microscopy and other cumbersomely termed diagnostic tools employed by conservators today to determine when and how a picture was made, the show may sound like homework.

But it isn’t; far from it. It’s one of those gems, which, amid the hard science, stumbles onto squishier truths about what we are really looking for when we look at art. Out to instruct us in the chemistry of painting, it ends up suggesting how elusive art remains despite all the gadgets that we devise to master it.

Continues at
http://www.nytimes.com/2010/07/13/arts/design/13abroad.html