Scientific dialogues for ... young people. Revised by J.W. Griffith

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Page 421 - ... as the angle of reflection is always equal to the angle of incidence, the image for any point can be seen only in the reflected ray prolonged.
Page 174 - Venus a pea, on a circle of 284 feet in diameter ; the Earth also a pea, on a circle of 430 feet ; Mars a rather large pin's head, on a circle of 654 feet ; the Asteroids, grains of sand, in orbits of from 1000 to 1200 feet; Jupiter a moderate-sized orange, in a circle nearly half a mile across...
Page 94 - To ask or search I blame thee not, for heaven Is as the book of God before thee set, Wherein to read his wondrous works, and learn His seasons, hours, or days, or months, or years.
Page 359 - The mercury is sustained in the tube by the pressure of the atmosphere on the surface of the fluid in the cup.
Page 390 - This will lead us to the explanation of one of the principal definitions in optics, viz. that the angle of reflection is always equal to the angle of incidence.
Page 242 - He first established the truth, that a body plunged in a fluid loses as much of its weight as is equal to the weight of an equal volume of the fluid!
Page 394 - If you place a candle before a looking-glass, and stand before it, the image of the candle appears behind it ; but if another looking-glass be so placed as to receive the reflected rays of the candle, and you stand before this second glass, the candle will appear behind that ; because the mind imagines...
Page 150 - Its situation with respect to the sun is much like that of the earth ; and by a rotation on its axis it enjoys an agreeable variety of seasons, and of day and night.

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