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40 Permeability of Electrical Light Wednesday May 10th 1843 The white wax was removed and its place sulphur with a cake of common bees wax unpurified was substituted in its place. The light still appeared through this, although it was just an inch and a half thick, and apparently impervious to the light of the day- The light was not however perfectly excluded from the inside of the tube as a small quantity entered between the end [[strikeout]] of the [[strikeout]] and the surface of the wax. The two lights howere were not conpounded with each other, that though the wax from the machine was red while, the other was the white light of day. [[image]] The defect in the arrangement mentioned in the last paragraph was remedied by fitting to the end of this tube a short cylinder of copper, and pressing the latter into the bees wax. With this, all extraneous light was cut off and the discharge [[strikeout]] through [[/strikeout]] appeared through of a beautiful red color like that of the sun through the fingers. The points in this experiment were placed at the distance of 3/4 of an inch from each other and 1/4 of an inch from the surface of the wax. Next the points were joined by a piece of wax softened so as to bury them in the substance of the [[mass?]], but the effect was not as great as with the [[strikeout]] wax [[/strikeout]] points at a ^small distance from the surface. The points were now removed to the distance of about two inches from the surface , the light through was still perceptible but very faint. [[end page]] [[start page]] Wednesday May 10th 1843 [[underlined]]electrical ligh[[/underlined]] [[underlined]] chemical emination[[/underlined]] 41 To compare this with the light of the clouds, [[strikeout]] wax [[/strikeout]]the same cake of wax with its tube was placed before a hole in a window shutter, and the light observed through. The effect was much stronger than I expected, the wax appeared of a beautiful crimson, and the [[strikeout]]intense [[/strikeout]] light was as intense as that from the discharge of the jar. From this result, it appears that there is nothing peculiar in the permability of wax for the electrical light. Whether the same is the case in reference to other substances,remains to be seen by experiment. Next placed a piece of wax a little yellower and thicker, before the end of the tube. The electrical light did not appear through this, although the light of the cloud was faintly perceptible. Resumed the experiments on the chemical rays: placed a prepared plate under the piece of wood pierced with holes, and brought over this the points used in the last experiments, but no impression could be produced on the plate from the electrical light, although the machine was turned for 5 or 6 minutes. The light from the clouds gave an impression on the same plate in the course of 20 seconds. This experiment combined with that of the phosphorescence, produced under the same circumstances mark a strong distinction between the chemical and phosphorogenic eminations. A series of different coloured glass was nex placed over the openings in the wooden block before mentioned, and these again over a prepared plate. The impression were very different. The order was as follows : [[underlined]]white[[/underlined]],[[underlined]] violet [[/underlined]], [[underlined blue[[/underlined]], (distinct), [[underlined]] green [[/underlined]], [[underlined]] salmon [[/underlined]], & [[underlined]]red [[/underlined]], no impression. The transparency of the green and blue was very nearly the same. [[end page]]
