520 
On Water and Air . 
[August, 
calculated to produce the effedt. I want to show you not 
only the transmission of gentle pressure, but the transmis- 
sion of a shock through water ; and if I hold this Rupert’s 
drop (d) in the bottle of water, and break off the tail, the 
Fig. 41. 
shock ought to be transmitted through the water, and if the 
experiment is successful the bottle will be broken. I will 
now break off the tail of the drop, and the bottle is broken 
to pieces. The breaking of the bottle is entirely due to the 
transmission of the force through the water. 
I introduce that experiment to your notice in order to 
make you understand another of far greater practical im- 
portance, and that is an experiment for which I am indebted 
to the obliging kindness of my friend Prof. Abel, of Wool- 
wich. I have no doubt that it will have an important future. 
Here is a bombshell, and I will pour water into that bomb- 
shell : it is very thick. Here is a small charge of powder, 
and we will explode that charge of powder in the middle of 
that bombshell filled with water. We place the shell for 
protection in a strong metal case. The force will be suffi- 
cient to break the bombshell, and I should not like even that 
small quantity of powder to have its way in this room with- 
out carefully covering it up. Two eledtric wires lead from 
a small fuze which is placed in the centre of the powder, 
and we will fire the charge by means of the eledtric current, 
and if the experiment is successful the shock will be trans- 
mitted to the water and burst the bomb. Now I will press 
