Chronograph Small 320×222 Medium 640×445 Large 1024×712 Download Tiff Original 2400×1668 | (1.5 MB) Description The chronograph is used to register time. Keywords chronograph, geodetic survey, surveying tool, tachymeter, transit instrument Galleries Miscellaneous Tools Source: Coast and Geodetic Survey: July 1, 1899, to June 30, 1900 (Washington, DC: United States Government Printing Office, 1901)