Decompression (diving) but in later experiments signs of what was later to become known as decompression sickness were observed. Later, when technological advances allowed the use of pressurization of mines and caissons to exclude water ingress, miners were observed to present symptoms of what would become known as caisson disease, compressed air illness, the bends, and decompression sickness. Once it was recognized that the symptoms were caused by gas bubbles, and that re-compression could relieve the symptoms, Paul Bert showed in 1878 that decompression sickness is caused by nitrogen bubbles released from tissues and blood during or after decompression, and showed the
Decompression theory relatively high gas phase volume which may be partly carried over to subsequent dives or the final ascent of a sawtooth profile. The function of decompression models has changed with the availability of Doppler ultrasonic bubble detectors, and is no longer merely to limit symptomatic occurrence of decompression sickness, but also to limit asymptomatic post-dive venous gas bubbles. A number of empirical modifications to dissolved phase models have been made since the identification of venous bubbles by Doppler measurement in asymptomatic divers soon after surfacing. One attempt at a solution was the development of multi-tissue models, which assumed that different