At supersonic speeds an aircraft adiabatically compresses the air in front of it. The expansion into vacuum proceeds adiabatically cooling the vapor. Finally, the simple Hamiltonian is adiabatically evolved to the desired complicated Hamiltonian. The calorimeter can be calibrated by adiabatically doing externally determined work on it. This proper, intrinsic hysteresis can be measured only if the rubber band is adiabatically isolated. Under high pressure, the air subsides (sinks) toward the surface, warming and drying adiabatically. Between 3 and 4 this hot gas expands, again approximately adiabatically. As winds blew across the "Mediterranean Sink", they would heat or cool adiabatically with altitude. In other words, it must respond adiabatically to its surroundings. An open system is not adiabatically enclosed.