Professor Edward L. Troxell, who is Connecticut's State geologist and teaches geology at Hartford's Trinity College, last week proudly exhibited the latest results of a lifetime spent thinking about rocks: a xylophone made of stone. The idea came to him on a trip through Virginia's Shenandoah Caverns when his guide produced a beautiful, clanking tone by striking a stalactite across the middle.
Fired with enthusiasm, Professor Troxell started looking for resonant rocks, found an ideal deposit of them in a 200-million-year-old lava bed atop Avon Mountain near his home in Hertford. Toting a load...