FREED FROM THE ACTION OF GRAVITY. 27 
tending to preserve the spherical form of the liquid mass, it ap- 
pears that the results must be analogous, if not identical, with 
respect to the figure which that mass assumes. 
In order to observe in all its beauty the phenomenon on which 
we are engaged, the handle must at first be turned with very 
little velocity,—a turn in five or six seconds ; the effects are then 
already very decided. If we afterwards apply a somewhat greater 
velocity,—for example, a turn in four seconds,—the flattening 
at the axis and the swelling at the equator are seen to be more 
considerable, and they are further augmented by increasing the 
velocity of the handle to one turn in three seconds. Before 
proceeding further, we may remark that in these experiments 
_ the handle must not be turned too long; for the mass of 
oil which in the first moments presents exactly a figure of 
revolution, eventually loses this form. At each fresh trial, 
therefore, the system must be left to repose; the oil then re- 
sumes its spherical form, and slowly, of itself, replaces itself in 
the proper position. The change of form which supervenes 
when too many turns are given to the disc, occasions results of 
a particular kind, and which are not without interest: I shall 
speak of them by-and-bye (§ 22). 
11. Now, if instead of moving the Fig. 3. 
handle slowly a considerable velocity 
is given to it, as two or three turns 
in a second, new and very curious 
phenomena are manifested. The 
liquid sphere first takes rapidly its 
maximum of flattening,then becomes 
hollow above and below around the 
axis of rotation, stretching out con- 
tinually in a horizontal direction, and finally, abandoning the 
disc, is transformed into a perfectly regular ring (fig. 3). 
This ring is rounded transversely, and appears to have a circle 
for its generatrix. At the moment of its formation its diameter 
increases rapidly up to a certain limit; when this is reached 
_ the movement of the disc must be stopped. The ring now 
remains for some seconds in the same state; then the resist- 
ance of the ambient liquid weakening its movement of rotation, 
it returns upon itself and ta back into a sphere around the 
disc and its axis. 
The velocity of the handle most suitable for producing a beau- 
— 
