The first of the Supplement volumes to be issued is Part 3 of the Technical Studies, the manuscript of which, after enduring many vicissitudes and lying hidden for decades, turned up in Weimar only in 1975, and appeared in print in 1983. The thematic index provides an overview of the entire material of all three volumes of the Technical Studies. This publication is available in two versions: bound in blue linen, or in grey boards. Only the former version contains the descriptions of sources and the critical notes.