Four-cycle internal-combustion engines having the supply and exhaust valves thereof located adjacent and in a single valve-chamber, the axes of such valves being parallel with the axial line of the working cylinder and both valves being positively operated, and reciprocating rods extending longitudinally of the engine and operated by and in unison therewith for operating such valves in the proper order to secure the continuous automatic operation of the engine, and similar arrangements of valves and operating means therefor but not shown in connection with all the elements necessary to form a complete and operative engine.
