A System of Natural Philosophy: In which the Principles of Mechanics, Hydrostatics, Hydraulic, Pneumatics, Acoustics, Optics, Astronomy, Electricity, Magnetism, Steam Engine, and Electro-magnetism, are Familiarly Explained, and Illustrated by More Than Two Hundred Engravings. To which are Added Questions for the Examinations of Pupils ...Robinson, Pratt & Company, 1813 - 340 σελίδες |
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Σελίδα 21
... described and illustrated all the uni- versal or inherent properties of bodies , and have also no- ticed the several kinds of attraction which are peculiar , namely , Chemical , Magnetic , and Electrical . There are still several ...
... described and illustrated all the uni- versal or inherent properties of bodies , and have also no- ticed the several kinds of attraction which are peculiar , namely , Chemical , Magnetic , and Electrical . There are still several ...
Σελίδα 54
... described by jets of water , under different degrees of pressure , are readily illustrated by tapping a tall vessel in several places , one above the other . 226. Suppose fig . 31 be such a vessel , filled with wa- ter , and pierced as ...
... described by jets of water , under different degrees of pressure , are readily illustrated by tapping a tall vessel in several places , one above the other . 226. Suppose fig . 31 be such a vessel , filled with wa- ter , and pierced as ...
Σελίδα 70
... described , the weight to be raised is on one side of the fulcrum , and the power on the other . Thus the fulcrum is between the power and the weight . 301. There is an- other kind of lever , in the use of which , the weight is placed ...
... described , the weight to be raised is on one side of the fulcrum , and the power on the other . Thus the fulcrum is between the power and the weight . 301. There is an- other kind of lever , in the use of which , the weight is placed ...
Σελίδα 72
... described three kinds of levers , and we hope , have made the manner in which each kind acts plain , by illustrations . But to make the difference between them still more obvious , and to avoid all confusion , we will here compare them ...
... described three kinds of levers , and we hope , have made the manner in which each kind acts plain , by illustrations . But to make the difference between them still more obvious , and to avoid all confusion , we will here compare them ...
Σελίδα 76
... described . 325. In cases where Fig . 58 . great weights are to be raised , and it is required that the machine should be as small as possible , on account of room , What is the capstan ? Where is it chiefly used ? What are the pe ...
... described . 325. In cases where Fig . 58 . great weights are to be raised , and it is required that the machine should be as small as possible , on account of room , What is the capstan ? Where is it chiefly used ? What are the pe ...
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16 feet angle appear ascertained atmosphere attraction ball body falls brittleness called centre of gravity centrifugal force centripetal force circle colours concave consequence convex lens convex mirror cylinder degrees descend diameter direction distance earth earth's axis earth's orbit eclipse elastic engine equal equator equinox Explain fig falling body fixed stars fulcrum glass heat Herschel inch inclined inclined plane increased length lens lever machine magnet mercury meridian miles moon motion move needle object orbit orifice particles pass pendulum perpendicular piece piston planets poles pounds pressure principle proportion pulley pump quantity rays of light reflected reflecting telescope refracted respect retina revolution revolve round row expresses Saturn screw seen side solar space specific gravity square steam substances sun and clock sun's Suppose surface telescope thrown tion tube upper valve velocity vessel visual angle weight wheel wire
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Σελίδα 161 - The circumference of every circle is supposed to be divided into 360 equal parts called degrees, and each degree into 60 equal parts called minutes, and each minute into 60 equal parts called seconds, and these into thirds, fourths, &c.
Σελίδα 171 - Different opinions have been advanced by astronomers respecting the cause of these appearances. By some, they have been regarded as clouds, or as openings in the atmosphere of the planet, while others imagine that they are the marks of great natural changes, or revolutions, which are perpetually agitating the surface of that planet. It is, however, most probable, that these appearances are produced by the agency of some cause, of which we, on this little earth, must always be entirely ignorant.
Σελίδα 121 - Lens is a transparent body, generally made of glass, and si shaped that the rays of light in passing through it are either collected together or dispersed. Lens is a Latin word, which comes from lentile, a small flat bean. It has already been shown, that when the rays of light pass from a rarer to a denser medium, they are refracted, or bent out of their former course, except when they happen to fall perpendicularly on the surface of the medium.
Σελίδα 23 - Thus, a tall body, shaped like fig. 27, will fall, if it. leans but very slightly, for the centre of gravity being far above the base, at a, is brought over the centre of motion, b,with little inclination, as shown by the plumb line.
Σελίδα 211 - The moon always presents the same face to us, by which it is evident that she turns but once upon her axis, while she performs a revolution round the earth ; so that the inhabitants of the moon have but one day and one night in the course of a lunar month. Since we always see the same hemisphere of the moon, the inhabitants of that hemisphere alone can see the earth.
Σελίδα 251 - M or Q, according to the position of the magnetic poles, or the direction of the current, as already explained. In either case it is thrown out of the mercury, and the galvanic circuit being thus broken, the effect ceases until the wire falls back again by its own weight, and touches the mercury, when the current being again perfected, the same influence is repeated, and the wire is again thrown away from the mercury, and thus the vibratory motion becomes constant.
Σελίδα 236 - The friction of the rubber against the glass plate (or cylinder) produces a transfer of the electric fluid from the rubber to the plate ; that is, the cushion becomes negatively and the glass positively electrified. The fluid which thus adheres to the glass, is carried round by the revolution of the cylinder ; and its escape being prevented by the silk...
Σελίδα 161 - The names of the 12 signs of the zodiac are, Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces. The...
Σελίδα 69 - ... completed, when a more awful hurricane burst upon them than the most experienced had ever braved. Nothing could withstand it; the sails already furled and closely bound to the yards, were riven away in tatters; even the...
Σελίδα 139 - REFRACTING TELESCOPE. — The most simple refracting telescope consists of a tube, containing two convex lenses, the one having a long, and the other a short, focal distance. (The focal distance of a double convex lens, it will be remembered, is nearly the centre of a sphere, of which it is a part.) These two lenses are placed in the tube, at a distance from each other equal to the sum of their two focal distances. Fig.