This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1871 Excerpt: ...bright lines belonging to sodium, hydrogen, &c, we consider that the sun is enveloped in a gaseous atmosphere which contains those substances in an incandescent state. Observations are now being constantly made by spectrum analysis, on the constitution of the heavenly bodies, and new discoveries follow in this ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1871 Excerpt: ...bright lines belonging to sodium, hydrogen, &c, we consider that the sun is enveloped in a gaseous atmosphere which contains those substances in an incandescent state. Observations are now being constantly made by spectrum analysis, on the constitution of the heavenly bodies, and new discoveries follow in this untrodden field of science. Interference.--The reader is referred to the remarks made under this head in Acoustics. Every undulation consists of a rise above, and a corresponding fall below, a horizontal line drawn from the beginning to the end of the wave. Now, if we conceive that a second wave overtakes a first one, so that the rise of the two waves shall occur at the same instant, there will be an increased wave, the rise will be higher. Now allow the second wave to overtake the first, so that the rise of one shall happen at the same moment as the fall of the other. Then the wave will be completely destroyed.-Again: any reflecting substance which is extremely thin, as, for instance, a soap-bubble, has wa es of light proceeding from the outer surface which suffer interference from the rays following them from the inner surface of the substance. In the case of waves of ether, when they are destroyed, the light is also destroyed. This is what is known as interference of light. By experiment it may be shown thus, --Into two holes near together in the shutter of a dark room put two pieces of red glass: two red cones of light will fall with their bases to the opposite side of the room, and be received on a white screen. The cones as they widen out interfere with each other, and the screen would receive the bases as in Fig. 62. The part A B C D would be found to contain alternate black and red bars; the red intense, the black produced by interference. ...
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Add this copy of The Elements of Acoustics, Light, and Heat to cart. $38.96, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2019 by Wentworth Press.
Add this copy of The Elements of Acoustics, Light, and Heat to cart. $56.29, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2019 by Wentworth Press.