92 Splashes. [Sess. 3 
‘Pearson’s Magazine,’— where two articles by Professor | 
Worthington on the subject appeared in July and August 
1898,—a number of illustrations prepared from the photo- 
graphs are here reproduced. (See Plates V.-X.) The follow- 
ing are Mr Cole’s explanations of the different stages of the 
splashes, and of the mode by which the photographs were 
taken. | 
The photographs were taken by Professor Worthington, F.R.S., 
and the lecturer, with a view to studying the phenomena of 
the splashes produced by drops of liquid and solid bodies 
falling into liquid. The splashes were made in a dark room, 
and illuminated by an electric spark from Leyden jars outside 
the room: previously a camera had been placed in position 
and focussed, and the sensitive plate exposed so that when 
the flash occurred the image was thrown on the plate. 
Electrically controlled arrangements were made, whereby the 
drops of liquid or the solid were released inside the dark room, 
and at the same time a metal ball was also released outside, 
which in falling discharged the Leyden jars and produced the 
required illumination of the splash. The heights of fall in 
both cases could be varied, thus enabling the height of fall 
of the liquid drop or of the metal ball to be varied, which 
permitted, on the one hand, the nature of the splash to be 
varied, and on the other hand the flash to be produced at any 
stage of the phenomenon required. From the photograph of 
a disc whirling so that its edge, which was graduated, travelled 
at the rate of 78 miles an hour, it was estimated that the 
duration of the flash did not exceed three millionths of a 
second. 
Several series of photographs were shown :— 
I. A drop of liquid falling 40 centimetres into water 
rendered visible by the addition of milk. The series of 
events are as follows: 1, A crater-like hollow of liquid is 
formed, with arms shooting out, and segmenting into drops. 
2, The crater subsides, and the arms die away. 3, The floor 
of the crater rises and shoots up in the centre, forming a 
thick column of liquid. 4, The column subsides, and a hole 
is formed ; meanwhile the liquid forming the column spreads 
out to form a plate whose edge constitutes the first outrushing _ 
ripple. 5, The column again rises and subsides; a second 
