  We present experimental investigations of antibubbles. Such an unusual fluid
object is a thin spherical air shell surrounding a liquid globule. We explain
how to produce them and we study their stability. By overweighting antibubbles
with a small amount of salt, they sink and pop at a definite depth. A critical
depth related to a critical pressure has been found. A modified Laplace law
describes the air shell thickness evolution with respect to pressure. This law
combined with surfactant layers interaction allows to explain the critical
depth for antibubble stability.
