Rufus Porter, inventor, muralist and founder of this magazine, saw a different opportunity than the average 49er. He wanted to ferry paying passengers from the East Coast to California via hydrogen airship, a huge craft that would make the trip in three days. Scientific American, however, is still going strong. But we are most interested in the sweep of scientific progress that Scientific American has spent nearly 18 decades covering. After all, when our first issue came out in 1845, the planet Neptune had yet to be discovered; today cosmologists soberly debate the existence of parallel universes.