, minute rays are shot out in
all directions on the surface. These are afterwards overflowed or
united, until, as in Fig. 8, the outline is only slightly rippled. Then
(Fig. 9) main rays shoot out, from the ends of which in some cases
minute droplets of liquid would split off, to be left lying in a circle
on the plate, and visible in all subsequent stages. By counting these
droplets when they were thus left, the number of rays was ascertained to
have been generally about 24. This exquisite shell-like configuration,
shown in Fig. 9, marks about the maximum spread of the liquid, which,
subsiding in the middle, afterwards flows into an annulus or rim with a
very thin central film, so thin, in fact, as often to tear more or less
irregularly. This annular rim then divides or segments (Figs. 14, 15,
16) in such a manner as to join up the rays in pairs, and thus passes
into the 12-lobed annulus of Fig. 16. Then the whole contracts, but
contracts most rapidly between the lobes, the liquid then being driven
into and feeding the arms, which follow more slowly. In Fig. 21 the end
of this stage is reached, and now the arms continuing to come in, the
liquid rises in the centre; this is, in fact, the beginning of the
rebound of the drop from the plate. In the case before us the drops at
the ends of the arms now break off (Fig. 25), while the central mass
rises in a column which just fails itself to break up into drops, and
falls back into the middle of the circle of satellites which, it will be
understood, may in some cases again be surrounded by a second circle of
the still smaller and more numerous droplets that split off the ends of
the rays in Fig. 9. The whole of the 30 stages described are
accomplished in about 1/20 second, so that the average interval between
them is about 1/600 second.

FIRST SERIES.

[Illustration: 1]

[Illustration: 2]

[Illustration: 3]

[Illustration: 4]

[Illustration: 5]

[Illustration: 6]

[Illustration: 7]

[Illustration: 8]

[Illustration: 9]

[Illustration: 10]

[Illustration: 11]

[Illustration: 12]

[Illustration: 13]

[Illustration: 14]

[Illustration: 15]

[Illustration: 16]

[Illustration: 17]

[Illustration: 18]

[Illustration: 19]

[Illustration: 20]

[Illustration: 21]

[Illustration: 22]

[Illustration: 23]

[Illustration: 24]

[Illustration: 25]

[Illustration: 26]

[Illustration: 27]

[Illustration: 28]

[Illustration: 29]

[Illustratio