Marking apparatus with multiple line capability

Apparatus for simultaneously forming one or more lines of multi-character messages on the surface of solid material which employs an array of marker pins which are moved by a carriage along a singular plane locus of movement defining a sequence of rows corresponding with a pixel matrix. The locus includes a retrace feature for each row or transverse movement which enhances the quality of character formation. An actuator assembly develops the locus of movement and, in turn, is driven by facing cam wheels which, in turn, are powered from an electric motor. A manifold which receives pneumatic pulses from arrays of conduits is coupled to the carriage and a marker head assembly, in turn, is removably coupled to the manifold. An array of solenoid actuated valves is coupled to the tubing arrays and to a pneumatic source which may be remotely positioned from the manifold.