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still in the basin, presenting, like the basin itself, the same side 

 of its circumference continually to the centre of the orbit Why 

 does it not rotate or seem to rotate like the water? If, as alleged, 

 the water does not rotate, does the more sluggish material, with 

 the basin that contains it, perform that operation, by virtue of a 

 rotary power naturally inherent in them ? These materials ex- 

 hibit the result which astronomers ascribe to rotation, yet keep 

 all the parts of their circumference in precisely the same relation 

 to the radius-vector, and to the line of revolution described by 

 the central axis of the mass ; while the wow-rotating water carries 

 every part of its circumference in succession past the radius-vec- 

 tor, which may be represented by a stick laid across the basin, 

 and the line of revolution, and through all the various degrees 

 of distance from the centre of the orbit, between its inner and 

 outer edges, as determined by the diametric breadth of the 

 moving body. Every pointof the water's circumference is seen suc- 

 cessively diverging from the line of the centre's orbital revolution, 

 and the sum of all these successive divergences amounts to a com- 

 plete rotation, or turning round of the body on its own axis or 

 centre. It is indeed impossible to account for the different re- 

 sults of the experiments when performed with water, from those 

 produced by the using of other substances, but by admitting the 

 real rotation of the water, whose liquidity enables its particles to 

 slip past each other in obedience to the impulse of the moving 

 power ; and denying the rotation of the basin and its more slug- 

 gish contents, whose particles are kept in their places, not by an in- 

 herent rotatory power, but by their %Dant of power to overcome the 

 friction that would instantly ensue among themselves, as well as 

 between them and the sides of the basin, were they to attempt to 

 move round about their centre like the water. Their adhesion, 

 cohesion, vis inertise, weight, or gravitation, is too great to be 

 overcome by the impulse of the moving power, while the lighter 

 particles of the liquid and unresisting water fly forwards at once 

 and continually till they get, all in their turn, round about the axis. 

 The experiment may be varied by placing a stratum of gravel 

 in the basin, and pouring the water above it. Then make the 

 basin revolve, and the liquid water will be seen as usual, moving 

 away round, while the sluggish gravel lies still. Which of the 

 two, the movable water or the immovable gravel, is the more 

 likely to rotate? The water unquestionably. Astronomers, how- 

 ever, think differently, and say, or at least to be consistent ought 

 to say, that it is the gravel, which rotates on its own axis, and 

 thereby ^^ brings the same point of its circumference continually 

 back to the radius," while the water keeps all its particles paral- 

 lel to themselves. But the gravel certainly does not possess any 

 inherent power of rotating in that direction, while the water 



