16 EXPLANATIONS. 



breaks and disappears, and the ring becomes 

 completely disengaged. The only observable dif- 

 ference between the latter and the ring of Saturn 

 is, that it is rounded instead of being flattened; 

 but this is accounted for in a satisfactory way. 



A little after the stoppage of the rotatory motion 

 of the disc, the ring of oil, losing its own motion, 

 gathers once more into a sphere. If, however, a 

 smaller disc be used, and its rotation continued 

 after the separation of the ring, rotatory motion 

 and centrifugal force will be generated in the 

 alcoholic fluid, and the oil ring, thus prevented 

 from returning into the globular form, divides 

 itself into " several isolated masses, each of which 

 immediately takes the globular form.'''' These are 

 " almost always seen to assume, at the instant of 

 their formation, a moveme?it of rotation upon them- ■ 

 selves — Si movement which constantly takes place 

 in the same direction as that of the ring. Moreover, 

 as the ring, at the instant of its rupture, had still 

 a remainder of velocity, the spheres to which it 

 has given birth tend to fly off" at a tangent ; but 

 as, on the other side, the disc, turning in the 

 alcoholic liquor, has impressed on this a move- 

 ment of rotation, the spheres are especially carried 



