18 was the mark used at this period by the painter Joseph Megerle.
This service which took four years to produce and consisted of 316 pieces. See J. Folnesics and E. W. Braun, Wiener Porzellan (Vienna 1907), pp. 150-151, and W.M. Razek and W. Neuwirth, Wiener porzellan (Vienna, n.d.), fig. 704.