1988 Dec. 1, Susan G. Sawyer, Photog Pewter the Time-Honored Way," New York Times (retrieved 5 July 2012)For quality control, Parliament in 1503 required all London-made pewter to be stamped with the maker's symbol or touchmark.
1876, W. H. H. Hudson, "On Observations made at San Antonio on the Total Solar Eclipse of 22 Dec. 1870", Proceedings of the Cambridge Philosophical Society: Mathematical and physical sciences, Volume 2, pp. 205-6:The instrument used was a refracting telescope by Dollond. . . . The cap containing the diaphragm was furnished with a touch-mark consisting of a projecting spoke. When in adjustment as described above this mark was parallel to the short side of the parallelogram.
1880, "Survey of the Albemarle and Chesapeake Canal", Report of the Chief of Engineers U.S. Army, p. 864:The initial touch-mark was established at Roper's saw-mill, on the North River, and is a point on 20-penny nail driven flush with the horizontal surface of sill to bull-wheel.
