Workshop journal/order book of clockmaker Johann Michael Landtwing (1688–1776)
The landscape-format manuscript has 133 pages (four of which are blank) and is held together by its front cover and a leather binding. The manuscript contains various notes and drawings (drafts, templates).
Johann Michael Landtwing’s (27/02/1688–17/09/1776) workshop journal is a rare document of considerable importance for the history of technology. It provides information on the career and maturing of an eminent Zug clockmaker, and its drawings (drafts, templates) and calculations allow us to follow Landtwing’s progress, as he develops new solutions starting out from a series of specific parameters. An impressive example of this is his grappling with the problem of striking mechanism that his father, Johann Peter Landtwing (1646–1726, clockmaker and coal merchant), built into one of his wall clocks. Johann Michael Landtwing tried to find his own solution to the problem of controlling the striking sequence on the hour and quarter hour using a single rack. One such solution, albeit a different one, was put forward in the “Encyclopédie, ou Dictionnaire raisonné des sciences, des arts et des métiers” by Denis Diderot (05/10/1713–31/07/1784) and Jean-Baptiste le Rond d’Alembert (16/11/1717–29/10/1783) (see also “Horlogerie, Pl. VI, in: Recueil de planches, sur les sciences, les arts libéraux et les arts mechaniques : avec leur explication, Troisième livraison, 298 Planches, Volume 21, Paris 1765”). Landtwing’s workshop journal is similar to those of Philipp Matthäus Hahn (25.11.1739–02.05.1790), a clergyman and inventor from Württemberg in Germany.
Johann Michael Landtwing learnt his craft in Augsburg. He later became Zug’s official clockkeeper and clockmaker and worked in Zug and its surrounding areas (St. Wolfgang, Unterägeri, Zug) and in Canton Aargau (Aristau, Bremgarten, Bünzen, Fahr, Muri). In 1718, he married Elisabeth Küchlin (died in 1767) from Diessenhofen (Canton Thurgau). One of the couple’s twelve children was Johann Anton Landtwing (1723–1802), who also became a clockmaker. From 1760 to 1763 and from 1771 to 1774, Johann Michael Landtwing served as Schultheiss (chief magistrate).
