Meteorological observations and essays / By John Dalton.

  • John Dalton
Date:
1834
Catalogue details

Licence: Public Domain Mark

Credit: Meteorological observations and essays / By John Dalton. Source: Wellcome Collection.

    108/280 (page 82)
    equilibrium of the atmosphere successively ; and he argues, that a current of air will constantly follow the extreme of heat, to restore the equi- librium,—and thus he accounts for the trade winds. It appears to me, however, that this conclusion is premature, and not warranted by the laws of motion. For, to simplify the conception, let us suppose a ring with a number of beads arranged upon it at equal distances, and, abstracting from the force of gravity, that each of them is endued with a repulsive power, in the same manner as are the particles of air. This supposition being made, let the principle of heat, or any other power, which acts simply by increasing their elasticity, act upon them in one part of the ring more than in another ; this will of course separate the particles in such part farther than they were before, and condense the others ; but it can never produce a rotatory mo- tion of the whole number of them round the ring, because the action being mutual, the motion gene- rated must be equal and contrary ;—or, in other words, no momentum of the whole mass of par- ticles around the ring, can be produced by any forces which they exert upon each other, agreeably to Newrton’s third law of motion.—We have here supposed the heat applied to one part of the ring only, but it is plain the same conclusion will obtain if it be applied to several parts at the same time, or successively, or in any other manner ; likewise if the addition of heat produce no momentum, the abstraction of it will not.