The original image was made in a homemade camera -- a 5x7 cigar box fitted with a simple Fresnel optic. I contact printed the paper negative and applied light to the developing print to achieve the Sabattier effect.
Thanks for the great feedback. The "camera" is embarrassingly simple: It's a Helix cigar box fitted with a credit card magnifier -- the Fresnel kind you can pick up at a stationery or office supply store. I expose onto Ilford RC paper. A green filter helps control the exposure -- ten to twenty seconds on a sunny day. Maybe I should print some more of these...