A System of Natural Philosophy: In which the Principles of Mechanics, Hydrostatics, Hydraulics, Pneumatics, Acoustics, Optics, Astronomy, Electricity, and Magnetism, are Familiarly Explained, and Illustrated by More Than Two Hundred Engravings : to which are Added Questions for the Examination of the Pupils : Designed for the Use of Schools and Academies |
From inside the book
Results 1-5 of 48
Page 16
... circle or ball is every where at the same distance from it . This difference is shown by fig . 1 , and it is quite obvious , that if the particles of matter are equally attracted to- wards the common centre , and are free to arrange ...
... circle or ball is every where at the same distance from it . This difference is shown by fig . 1 , and it is quite obvious , that if the particles of matter are equally attracted to- wards the common centre , and are free to arrange ...
Page 25
... circle is supposed to be the circumference of the earth , a , the ball falling towards its upper surface , where we stand ; b , a ball falling to- wards the opposite side of the earth , but ascending in re- spect to us , and d , a ball ...
... circle is supposed to be the circumference of the earth , a , the ball falling towards its upper surface , where we stand ; b , a ball falling to- wards the opposite side of the earth , but ascending in re- spect to us , and d , a ball ...
Page 43
... circle . The force by which a body tends to go off in a straight line ) is called the centrifugal force ; that which keeps it from fly- ing away , and draws it towards the centre , is called the cen- tripetal force . Bodies moving in ...
... circle . The force by which a body tends to go off in a straight line ) is called the centrifugal force ; that which keeps it from fly- ing away , and draws it towards the centre , is called the cen- tripetal force . Bodies moving in ...
Page 44
... circle , the greater will be the force with which it will fly off in a right line . Thus , when one wishes to sling a stone to the greatest dis tance , he makes it whirl round with the greatest possible ra- pidity , before he lets it go ...
... circle , the greater will be the force with which it will fly off in a right line . Thus , when one wishes to sling a stone to the greatest dis tance , he makes it whirl round with the greatest possible ra- pidity , before he lets it go ...
Page 47
... circle , the centre of which is at the extremity of the base on which the body stands . This will be comprehended by fig . 23 . a Fig . 23 . d Suppose the figure to be a block of marble , which is to be turned over , by lifting at the ...
... circle , the centre of which is at the extremity of the base on which the body stands . This will be comprehended by fig . 23 . a Fig . 23 . d Suppose the figure to be a block of marble , which is to be turned over , by lifting at the ...
Common terms and phrases
air pump angle appear atmosphere attraction axis balance ball barometer barrel boat bulk called centre of gravity centrifugal force circle colors common concave mirror consequence convex lens convex mirror degrees descend diameter direction distance earth eclipse elastic electric equal equator exactly Explain fig falling body feet filled fluid fulcrum glass greater heat hence hydrometer illustrated inches inclined plane increased instrument kind of lever length lens less machine magnetic mercury meridian metals miles moon motion move object obliquely orifice particles pass pendulum perpendicular piece pipe piston poles pounds pressure principle proportion pulley quantity of matter raised rays of light reflected reflecting telescope refracted respect retina revolution revolve rise rope round screw seen side space specific gravity stars substances sun's Suppose surface suspended telescope thrown tion tube turned upwards valve velocity vessel vibrations visual angle weight
Popular passages
Page iv - In conformity to the act of Congress of the United States, entitled, " An act for the encouragement of learning, by securing the copies of maps, charts and books, to the authors and proprietors of such copies, during the times therein mentioned ;
Page iv - BBOWN, of the said district, hath deposited in this office the title of a book, the right whereof he claims as author, in the words following, to wit : " Sertorius : or, the Roman Patriot.
Page 128 - ... proceeding, when the captain's order came to prepare with all haste for a storm. The barometer had begun to fall with appalling rapidity. As yet, the oldest sailors had not perceived even a threatening in the sky, and were surprised at the extent and hurry of the preparations: but the required measures were not completed, when a more awful hurricane burst upon them than the most experienced had ever braved.
Page 236 - ... by which it is illustrated, that the sun constantly shines on a portion of the earth equal to 90 degrees north, and 90 degrees south from his place in the heavens, and consequently, that he always enlightens 180 degrees, or one half of the earth. If, therefore, the axis of the earth were perpendicular to the plane of its orbit, the days and nights would...
Page 232 - It has already been explained, that the ecliptic is the plane of the earth's orbit, and is supposed to be placed on a level with the earth's horizon, and hence, that this plane is considered the standard, by which...
Page 128 - ... 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 bare yards and masts were in great part disabled; and at one time the whole rigging had nearly fallen by the board.
Page 18 - The intensity of light is found to increase and diminish in the same proportion. '^Thus, if a board a foot square, be placed at the distance of one foot from a candle, it will be found to hide the light from another board of two feet square, at the distance of two feet from the candle.
Page 290 - By connecting together a sufficient number of these jars, any quantity of the electric fluid may be accumulated. For this purpose all the interior coatings of the jars are made to communicate with each other, by metallic rods passing between them, and finally terminating in a single rod. A similar union is also established, by connecting the external coats with each other. When thus arranged, the whole series may be charged, as if they formed but one jar, and the whole series may be discharged at...
Page 215 - Different opinions have been entertained by astronomers respecting the cause of these belts and spots. By some they have been regarded as clouds, or as openings in the atmosphere of the planet, while...
Page 285 - 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...