The science of light-production may be considered to have been born in the latter part of the eighteenth century and beginning with that period a few chapters treat of the development of artificial light up to the present time. Until the middle of the nineteenth century mere light was available, but as the century progressed, the light-sources through the application of science became more powerful and efficient. Gradually mere light grew to more light and in the dawn of the twentieth century adequate light became available. In a single century, after the development of artificial light began in earnest, the efficiency of light-production increased fifty-fold and the cost diminished correspondingly.
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