h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Before Tombaugh started his search another man was hard at work on the problem.
the Oxford dictionary of Scientists says in part
He calculated its orbit and position, beginning his search in 1905. He published his negative results in 1914. Fourteen years after his death Clyde Tombaugh, observing at the Lowell Observatory in 1930 and using a blink comparator, discovered the new planet. It was named Pluto since like the god it ruled as prince of outer darkness but also because its first two letters stood appropriately for Percival Lowell.