The unity of the physical sciences : being an inquiry into the causes of gravitation and polarity, with an application of the results to some of the principal phænomena in each of the physical sciences / by John Dickson.

  • Dickson, John, 1974-
Date:
1859
Catalogue details

Licence: Public Domain Mark

Credit: The unity of the physical sciences : being an inquiry into the causes of gravitation and polarity, with an application of the results to some of the principal phænomena in each of the physical sciences / by John Dickson. Source: Wellcome Collection.

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    outwards must remain unchanged, being merely diflPased through a gi-eater space as the distance from the centre in- creases ; therefore, so long as the force obeys this law, no recoil or retiu'n force can be generated causiag the particles of the medium to return to their former position; for, if there were, the total force moving outwards would be decreased thereby. Beyond the limits within which the force obeys this law, there must therefore be a space in which the force obeys an- other law, and in which the recoil or return force is generated; for if there is no return force there can be no medium. 5. At the greatest distance, however, to which observation has yet extended, all the forces which emanate from the atoms of matter have been found to obey this law; hence the distance from the centre at which this return force is generated must be immeasurably great. The motion of the particles of the medium cannot then be considered as a progressive vibratory motion; that is, if A, B, C, be consecutive particles, A cannot be considered as first moving from and to the centre, then B, then C; but precisely as A must have been in motion from the centre, before B could commence to move in that direction, so must B have been ia motion to the centre before A could return to it. Thus, although the one force may be a conse- quence of the other, yet, practically speaking, they are inde- pendent forces, the cessation of the one not involving the immediate cessation of the other. Thus, supposing that in the space beyond an interposing body all force moving out- ward has ceased, yet, in this space, the force moving inward may not have ceased. 6. These two forces being equal, whatever etfeet the force moving outwards produces on a body when impinging on it must also be produced, in like circumstances, but in an oj)po- site direction, by the force moving inwards. 7. If, then, there be in reality an elastic medium, and if any of the phaenomena of nature are produced by motions im- pressed on its particles, then, so far as these phaenomena are