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Show ai-P"" V Jv&vrnotviJ Wood Photographing Itself. A ciiriuus pnq rty of wood, whereby where-by It Is a hi- ki photograph Itself a the dark Is ri-rrlhd by Dr William J Kuasell In a paper recently read before be-fore the lmdon Koyal society This property he showed by iperlmaiiu to belong probably to all wooda, ttoaa woods howeter being much mora i. tlve than others To obtain at picture the wood must be In contact with or at a little dlatanre above tb photo-graphic photo-graphic plate, and moat remain tbere for times varying from bait an hour to eighteen houra and be at a tempata lure not higher than 111 degrees Pa),, renhelt The wood of the conifers It very active and give picture which are very definite It wat thought that this action a due to the reslaout bodies In the wood but It hat bn r marked that there I no action rrom the dark autumn wood. Itetln etlsts In the dark rlnga, but apparent, ly under such conditions that Ha action cannot eacape Arid again with the spruces the action on the plate Is mil mi definite With regard to woods nthir than conifers, oak and beech are both, active nnd give vary good pictures as do alao acncla (ltob. nisi. Spanish chestnut and sycamore. On the other hand, nth, elm, horse chestnut and plane are. In comparison, but slightly active. Knots In a wood generally, but nut alway give a good picture |