ROENTGEN RAYS AT THE UNIVERSITY OF MINNESOTA. 1. Watch and chain. 2. College badges in mahogany box. 3. Copper coin. 4. Weights in heavy velvet-lined mahogany box; blank space contains aluminum. 5. Coins in inner pocket of heavy seal purse. 6 and 7. Colored glass. 8. Key 9. Lead-pencil. _West. Elect._, Mar. ’96. ]
Edison stated that the following substances were among those which fluoresced more or less under the action of the X-rays. Mercurous chloride, mercury diphenyl, cadmic iodide, calcic sulphide, potassic bromide, plumbic tetrametaphosphate, potassic iodide, plumbic bromide, plumbic sulphate, fluorite, powdered lead glass, pectolite, sodic cressotinate, ammonic salicylate, and salicylic acid. Compared with the above, the following fluoresced less. Powdered German glass, baric, calcic and sodic fluorides, sodic, mercuric, cadmic, argentic and plumbic chlorides, plumbic iodide, sodic bromide, cadmic and “cadmium, lithia bromide, mercury, cadmium sulphate,” uranic sulphate, phosphate, nitrate, and acetate, molybdic acid, dry potassic silicate, sodic bromide, wulfenite, orthoclase, andalucite, herdinite, pyromorphite, apatite, calcite, danburnite, calcic carbonate, strontic acetate, sodic tartrate, baric sulphobenzoic, calcic iodide, and natural and artificial ammonium benzoic. Not one of all the 1800 crystals and precipitates fluoresced through a thick cardboard under the influence of the arc light, 16 inch spark in air, a vacuum tube so highly exhausted that a 10 inch spark left it dark, nor the direct rays of the sun at noon time. As calcic tungstate was phosphorescent by friction, he theorized that the X-ray is a wave due to concussion.
Flame sensitive to X-rays. Edison stated that his assistants submitted the sensitive flame and the phonographic listening tube to the action of the X-rays, and found that they were responsive thereto.
133. X-RAYS APPARENTLY PASSED AROUND A CORNER. Referring to the figure “X-ray Diffusion Fig. 1”, p. 129, it will be noticed that there were three principal elements. First a discharge tube, then a thick steel plate and then a sciascope, all arranged in the proportion indicated in the figure, where the sciascope was within six inches of the edge of the plate, “well within the shadow” thereof. § 69. Fluorescence was seen under these conditions. When the sciascope was directly behind the middle of the plate and opposite the discharge tube, there was no fluorescence, showing that the plate was thick enough to cut off all the rays and therefore the energy must have traveled in two directions for some reason or other.