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الصفحة 81 - The singing of most birds seems entirely a spontaneous effusion, produced by no exertion, or occasioning no lassitude in muscle, or relaxation of the parts of action. In certain seasons and weather, the nightingale sings all day, and most part of the night ; and we never observe that the powers of song are weaker, or that the notes become harsh and untunable, after all these hours of practice.
الصفحة viii - it seems probable that God in the beginning formed matter in solid, massy, hard, impenetrable, moveable particles, of such sizes, figures, and with such other properties, and in such proportion to space, as most conduced to the end for which he formed them, and that these primitive particles, being solids, are incomparably harder than any porous bodies compounded of them ; even so very hard as never to wear or break to pieces ; no ordinary power being able to divide what God himself made one in the...
الصفحة 295 - It is a curious sight to see a piece of wood, or of beef, or an apple, or a bottle of water repelled by a magnet, or taking the leaf of a tree and hanging it up between the poles, to observe it take an equatorial position. Whether any similar effects occur in nature among the myriads of forms which...
الصفحة 285 - ... the electricity which decomposes, and that which is evolved by the decomposition of, a certain quantity of matter, are alike.
الصفحة 328 - Q. How is HEAT evolved by combustion ? A. By chemical action. As latent heat is liberated, when water is poured upon lime, by chemical action ; so latent heat is liberated in combustion, by chemical action also.
الصفحة 7 - If a passenger leap from a carriage in rapid motion, he will fall in the direction in which the carriage is moving at the moment his feet meet the ground ; because his body, on quitting the vehicle, retains, by its inertia, the motion which it had in common with it. When he reaches the ground, this motion is destroyed by the resistance of the ground to the feet, but is retained in the upper and heavier part of the body ; so that the same effect is produced as if the feet had been tripped.
الصفحة 30 - ... other side, and the spring has to begin its work again. The balance-wheel at each vibration allows one tooth of the adjoining wheel to pass, as the pendulum does in a clock ; and the record of the beats is preserved by the wheel which follows.
الصفحة 84 - According to this law, any irregular surface must break an echo; and if the irregularity be very considerable, there can be no distinct or audible reflection at all.
الصفحة 72 - The vibrations of the membrane of the drum are conveyed further inwards, through the cavity of the drum, by a chain of four bones (not here represented on account of their minuteness), reaching from the centre of the membrane to the oval door or window, leading into the labyrinth e.
الصفحة 105 - No ; but we consider clothing warm or cool according as it impedes or facilitates the passage of heat to or from the surface of our bodies. The thick cloak which guards a Spaniard against the cold of winter is also in summer used by him as a protection against the direct rays of the sun...

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