. The Annual of scientific discovery: or, Year-book of facts in science and art. Industrial arts -- Yearbooks; Science -- Yearbooks. 134 ANNUAL OF SCIENTIFIC DISCOVERY. matic or solar spectrum. (See figure.) When the solar spectrum is received upon a white screen, it appears at first glance to be a contin- uous band of colored light (red, orange, yellow, green, blue, indigo,. and violet); but by taking certain precautions, the luminous band may be seen in reality to be traversed in the direction of its breadth by numerous dark lines, varying, however, in different parts, in width and distinctn
. The Annual of scientific discovery: or, Year-book of facts in science and art. Industrial arts -- Yearbooks; Science -- Yearbooks. 134 ANNUAL OF SCIENTIFIC DISCOVERY. matic or solar spectrum. (See figure.) When the solar spectrum is received upon a white screen, it appears at first glance to be a contin- uous band of colored light (red, orange, yellow, green, blue, indigo,. and violet); but by taking certain precautions, the luminous band may be seen in reality to be traversed in the direction of its breadth by numerous dark lines, varying, however, in different parts, in width and distinctness; these lines are independent of the nature of the re- fracting medium used, and they always occur in the same color and at corresponding parts of the spectrum. The position of some of the most conspicuous lines observed in the solar spectrum was long ago accurately determined by Fraunhofer, who designated them by the letters 5, (7, Z>, E, F, G, and H, as represented in the figure. It has also been long known that the position of these dark lines varies with the source of the light yielding the spectrum; the spectrum yielded by solar light having one system of lines, and the spectrums from other or artificial lights having other systems or peculiarities. It is at this point that the investigations of Messrs. Bunsen and Kirchhoff may be properly said to have commenced. They found that when a metallic or other elementary substance is burned or evap- orated in a gas flame, and the light of the flame is passed through a prism and refracted to form a spectrum, the spectrum so formed has bright lines crossing it, which are peculiar to or characteristic of the metal or element present in a state of vapor in the flame yielding the light; or, in other words, the light from one metal or element will present lines in one part of its spectrum, and that from another metal lines in a different part; the light of each metal or element having always its own characteristic lines with inva
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Keywords: ., bookcentury1800, bookdecade1860, booksubjectindustrialartsyearbo
