. Journal of electricity . aresomething more than technicalities and that theyshould be eliminated, to observe that correct spacingunits insures uniformity of illumination, to learnsomething of color quality and light direction, andfinally, that the phrase too much light has its ori-gin in too much glare. Figure 3 shows a close-up view of the stage. Asmall platform was erected across the front of theroom and the control of all lighting units brought toa switchboard at this point. A rheostat in the main modified as to reduce the gradation in size betweenrows of letters, stood on a table. In add
. Journal of electricity . aresomething more than technicalities and that theyshould be eliminated, to observe that correct spacingunits insures uniformity of illumination, to learnsomething of color quality and light direction, andfinally, that the phrase too much light has its ori-gin in too much glare. Figure 3 shows a close-up view of the stage. Asmall platform was erected across the front of theroom and the control of all lighting units brought toa switchboard at this point. A rheostat in the main modified as to reduce the gradation in size betweenrows of letters, stood on a table. In addition therewas provided a shutter-like device for instantan-eously exposing a desired letter or group of lettersto view. At one side of the stage was a row of lamps withclear bulbs, diffusing bulbs, diffusing globes, etc., foruse in analyzing glare. Near this was placed a chartwith lettering of various sizes and near the bottom acircular opening behind which was placed a 300-wattall-frosted lamp connected with a Fiff. -View of stage showing apparatus in illustrating the various illumination principles. circuit permitted a reduction of voltage of the vari-ous systems to a large range below normal. At theback of the platform was a long box lined with clothand open at the front, in which were three verticalwooden bars of dilfeient cross sections, and lightingcircuits providing illumination from any or all direc-tions. A screen for the projection of lantern slideswas placed above this box. Above and to the front of the stage wasmounted a 200-watt floodlight with its beam directedon the stage. A rheostat was placed in series withthis lamp so that the intensity of illumination on thestage could be varied at will. A large card in the form of a Snellen Chart, so A large chart showing a plan view of the roomwith the different systems of lighting ancl indicatingthe position of the various tables was available indiscussing the results obtained. A blackboard com-pleted the platf
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectelectricity, bookyear
