In this podcast, Mark and Jack share stories about the "hard- luck" Swedish chemist, Carl Scheele. Not given the accolades of scientists like Antionne Lavoisier and Joseph Priestly (the two scientists generally given credit for the discovery of oxygen) Scheele's contributions can be shown to be perhaps even more significant in the discovery of this life-giving element. Discussions concerning the role of oxygen in burning add to the story told so that listeners will come away with a good understanding of the chemical process called combustion.