First Lessons in Physics

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Hendricks & Chittenden, 1871 - 172 sivua
 

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Sivu 106 - It can engrave a seal, and crush masses of obdurate metal like wax before it — draw out, without breaking, a thread as fine as gossamer, and lift a ship of war like a bauble in the air. It can embroider muslin, and forge anchors, cut steel into ribands, and impel loaded vessels against the fury of the winds and waves.
Sivu 106 - ... is as nothing to it. It can engrave a seal, and crush masses of obdurate metal before it ; draw out, without breaking, a thread as fine as gossamer, and lift a ship of war like a bauble in the air. It can embroider muslin and forge anchors, cut steel into ribbons, and impel loaded vessels against the fury of the winds and waves.
Sivu 173 - ... just enter them when some little pressure is used. (If much pressure is used, the tube is not unlikely to break, and the splinters of glass may cause injury. The hole should never be so much smaller than the tube as to make it necessary to use much force in passing the latter through it. It Is a good plan, also, to wrap the tube in a cloth or handkerchief while it is being inserted in the cork.) Now pass the longer of the two tubes through the cork, with moderate pressure and a twisting motion,...
Sivu vi - Physics lies at the foundation of all science; and if nothing else were taught, it would be a great gain to have the youth of this country soundly instructed in the laws of the elementary forces — gravitation, heat, light, and so forth. The purely physical sciences furthermore have the great practical advantage that they can be pursued to a great extent without what have been felicitously termed "stinks or messes...
Sivu 173 - Fig. 22. straight through the cork, so that it may be truly central. Of the proper direction the eye will be the best judge : and when the cork-borer has penetrated some little way, it will be advisable to turn the cork a quarter round, in order that it may be seen whether the axis of the cork-borer and of the cork are still in the same straight line. If not, a slight pressure on the cork-borer in one direction or the other, while the boring is continued, will set it straight.
Sivu 38 - Divisions of Matter. — Three divisions of matter are recognized in science : masses, molecules, and atoms. A Mass of matter is any portion of matter appreciable by the senses. A Molecule is the smallest particle of matter into which a body can be divided without losing its identity.
Sivu 100 - The bulb is therefore heated, when the air within expands, and a portion escapes in bubbles through the mercury. On cooling, the pressure of the external atmosphere forces a quantity of mercury through the tube into the bulb. By repeating this operation a few times, the bulb and a portion of the tube are filled with mercury. The whole is then heated till the mercury boils, thus filling the tube, when the funnel is melted off and the tube hermetically sealed by means of a jet of flame urged by a blow-pipe.
Sivu 172 - When the proper bend is completed, lay the tube on a bit of glass in such a position that the heated portion does not come into contact with any cold surface, and leave it to cool slowly.
Sivu 94 - Why are steam-chests and steam-cylinders often covered with wood ? 5. Why are the walls of safes often filled with fine ashes ? 6.
Sivu 173 - Take a cork-borer rather smaller than the tubing which you have; see that the holes do not run into each other, or pierce the side of the cork. The holes should next be smoothed and slightly enlarged by a rat-tail file, until the end of one of the tubes will just enter them when some little pressure is used. (If much pressure is used, the tube is not unlikely to break, and the splinters of glass may cause injury. The hole should never be so much smaller than the tube as to make it necessary to use...

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