ORIGINAL PATENT APPLICATION NUMBER 139,224 FOR IMPROVEMENTS IN OR CONNECTED WITH MECHANICAL MEANS AND INSTRUMENTS FOR MEASURING VERTICAL HEIGHTS OR AERIAL TARGETS OR HORIZONTAL DISTANCES, SAY, FOR SURVEYING PURPOSES.

Name: ORIGINAL PATENT APPLICATION NUMBER 139,224 FOR IMPROVEMENTS IN OR CONNECTED WITH MECHANICAL MEANS AND INSTRUMENTS FOR MEASURING VERTICAL HEIGHTS OR AERIAL TARGETS OR HORIZONTAL DISTANCES, SAY, FOR SURVEYING PURPOSES.
Author: Archibald Barr & William Stroud (inventors). Barr and Stroud Limited
ISBN: 978B000O719F3