VIRCHOW AND EVOLUTION. XVI. THE ELECTRIC TELEGRAPH. Needle instruments--Influence of current on, 129. Mainspring, invention of, 59. Compound locomotives, 62. Compound microscope, 261. Condenser, marine, 71, _72_; of Ruhmkorff coil, 123. Conduit, 176. Convex lens, image cast by its complete combustion in air but in the Coronation Chapel, lean.