He recently decided to show his pupils the potential damage they would inflict on their lungs if they became smokers. He placed a previously healthy pig's lung in a sealed perspex box, and hooked it up to a pump which enabled the tissue to artificially take in and then expel air. He then added a regular cigarette and lit it, allowing the smoke to enter the lungs. The video shows that this was repeated with 60 cigarettes before comparing the lung tissue with lungs from another pig.