The principles of mechanics: designed for the use of students in the University / [James Wood].

  • James Wood
Date:
1796
Catalogue details

Licence: Public Domain Mark

Credit: The principles of mechanics: designed for the use of students in the University / [James Wood]. Source: Wellcome Collection.

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    or which by it’s gravity will produce the fame effedt, under the fame circumftances, is alfo called a pound ; and thefe two together, two pounds, &c. Gravity is not an accidental property of matter arifing from the figure or difpoiition of the parts of a body; for then, by changing the fhape, or altering the arrangement of the particles, the gravitation of the mafs would be altered. But we find that no fepa- ration of the particles, no change of the ftrudture, which human power can effedt, produces any altera- tion in the weight. As gravity is a property belonging to every particle of a body, independent of it’s fituation with refpedt to other particles, the gravity of the whole is the aggregate of the gravities of all it’s parts. Thus, though the weight of the whole is not altered by any divifion, or new arrangement of the par tides, yet every increafe or diminution of their number, produces a correfpond- ing increafe or diminution of the weight. Our prefent fubjedt does not lead us to confider gravitation in any other point of view than fimpiy as a tendency in bodies to the center of the earth, or to attend to it’s effedls at any confiderable diftance from the furface ; it may not, however, be improper to obferve that the operation of this principle is much more extenfive. Every portion of matter gravitates towards every other portion, in that part of the fyftem ' of nature which falls under our obfervation. The gravitation indeed of fmall particles towards each other is infenfible, on account of the fuperior adtion of the earth j* yet it has been found, by the accurate obfervations • The common experiment of two particles of the fame kind, as
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