For the manufacture of acetylene and synthesis or reduction gas from coal by means of an electric arc or plasma process, coal converted into powder form is pyrolyzed in an electric arc reactor with an energy density of 1 to 5 kWh/Nm.sup.3, a residence period of 0.5 to 10 msec and at a temperature of at least 1500.degree. C. such that the gaseous compounds derived from the coal do not exceed 1.8 times the so-called volatile content of the coal. The coke remaining after subsequent quenching is then fed to a second electric arc reactor in which the coke, by means of a gasifying medium in conjunction with heating by means of an electric arc or plasma process, is converted into synthesis or reduction gas furing a residence period of 1 to 15 sec and at a temperature of at least 800.degree. C. The gas flow from the pyrolysis zone is cleaned and acetylene is recovered therefrom by selective solvents. The gas from the cleaning stage is similarly cooled and cleaned.