I love this song. To me, it’s always been about how the joy of scientific discovery mirrors the joy of religious discovery.
Plus, as I realized after years of listening to it, it’s got a great play on words in there (about that very thing). He talks about oxygen as in “priestly green,” which can also be heard as “Priestly green”. Joseph Priestley was the guy who discovered oxygen using green plants. And priests wear green during ordinary liturgical time, as a symbol of hope.