Description: Master Mechanic's Letterbook, containing copies of letters by Mr. Jacob Johann (employee of the Wabash Railway & President of the American Railway Master Mechanic's Association, 1886-87) to the chairmen & secretaries of the Association's committees, committee circulars, original letters to Johann, and drawings related to railroads & locomotives. Letters relate to balanced slide valves; the best form & materials for locomotive wheels, axles, & bearings' cast iron & steel tire wheels; construction & maintenance of railway rolling stock; driver brakes; higher economy in use of bituminous coal for locomotives; hydraulic tests; improvement in valve gears; locomotive boiler construction & comparative performance of locomotives; lubricants; removing, cleaning & resetting of flues; safety features & economy measures; shop tools; smoke stacks & spark arresters; standard draw bars; standard driving wheel centers & standard section of tires & steel castings for locomotives. Items of special interest include 1) July 14, 1880 letter from James Boon (chairman of the ARMMA's Committee on Investigations to Johann, requesting assistance in gathering information for a report (pp.136-137); 2) Formula for successful locomotive engineering, April 17, 1884 (pp. 304-306); 3) Obituary for Charles A. Smith, associate member of the ARMMA & Professor of Civil & Mechanical Engineering, Washington U., St. Louis, Feb. 2, 1884 (pp.395-398), 4) Drawings by Mr. Johann (pp.438-439). 5) Circular from 4th Vice-President of Wabash, St. Louis & Pacific Railroad on Value of the Missouri Pacific's Railway Hospital System (p.480).