. "Section 124, acts Oct. 6, 1917, ch. 83, ??4, 40 Stat. 386; Dec. 26, 1941, ch. 633, ??2, 55 Stat. 864, authorized a superintendent, foreman, or other duly authorized employee at a mine, quarry, or other work, when licensed, to sell or issue to any employee under him such amount of explosives or ingredients required by that employee in performance of his duties." . . . .