Two diaries marked ‘diary number 1’ dated 1845 and 1847 of Peter John Margary (1820-1896). The first diary mainly documents the construction of the Exeter-Powderham contract whilst the second diary documents work concerning atmospheric engine houses. The diaries include details of the construction of bridges, viaducts, stations and reservoirs including accounts of the Powderham Topsham railway station, the Exe bridge, Dainton siding and reservoir and the St Thomas viaduct.

The diaries include accounts of Margary working at the office in his house in Dawlish, meetings with ‘Mr. Brunel’ at his office in Duke Street, they note dealings with other engineers of the South Devon Railway including Messrs Hammond, Harrison, Glennie. They include accounts of travelling on the atmospheric railway and on mail trains, accounts of frequent visits to atmospheric engine houses including Starcross and Torquay, details of meetings with men from Boulton and Watt to set up engines in Atmospheric engine houses.