Earlier this month, I pointed to a New York Times preview of “The Perfect Medium: Photography and the Occult” at New York’s Metropolitan Museum of Art. Today’s NYT takes a deeper look at the exhibition with a long review and narrated slideshow by Michael Kimmelman. (Seen here, detail of “Henri Robin and a Specter” (1863) by Eugene Thibault.) 
From the text:
The exhibition’s deeper subject is the dreamer in all of us. The art in these ham-fisted photographs of transparent tomfoolery, such as it is, is generally not formal but mystical. I don’t mean that the images of spirits and ectoplasms and mediums lofting card tables into the air are believable (although they are, I suppose, if you wish them to be). I mean that they inevitably sail past their intended goal, which is to document the unbelievable, and end up in a realm of higher truth. They remind us that art is a wonderment defying logic.
How else to describe, except in terms of wonderment, the deliciousness of the implausible image of the French medium Marguerite Beuttinger accompanied by her twin spirit, a trick of double exposure that evidently fooled somebody at one point. A blurry Marguerite is standing beside a seated Marguerite whose body is so slight that it makes her look like her own dwarf twin. The effect is marvelous, as is the multiple exposure of the ghost of Bernadette Soubirous, in white robes, gliding under a trellis, gradually evaporating into a brick wall.