All of the letters in this series were sent to Jane Hackworth (nee Golightly) from her husband Timothy Hackworth, the exception being a letter from Jane Young (nee Hackworth), Jane and Timothy Hackworth’s youngest daughter’s teacher. Letters are largely about business matters and show how Hackworth involved his wife in his business activities; his shares key business events with his wife and often goes into detail about technical and procedural railway matters, he also asks her to carry out tasks and pass on messages to his business colleagues.

Earliest letters originate from when Hackworth was just about to leave his position at Warbottle for the Stockton and Darlington Railway. A letter from 1836 describes John Wesley Hackworth, Timothy Hackworth’s son leaving for Russia where he delivered the first locomotive in Russia. Letters from the 1840’s describe Timothy Hackworth’s activities running his business at Soho Works.

Correspondence focuses on Timothy Hackworth’s work for the London and Brighton Railway Company, with many letters sent from London whilst Hackworth was in discussions with the company. Letters mention John Gray, locomotive superintendent. Hackworth often discusses machinery that he was acquiring at Soho Works to assist with the manufacture of engines. Letters show difficulties that Hackworth was facing during the order for the company, with references borrowing money and the company’s slowness in paying him. Letters from 1849 refer to Sanspareil 2 and show increasing money problems. In a letter from 1849, a year before Hackworth’s death, he declared to his wife that the railway world was 'getting worse and worse’'.

The series is also peppered with insights into day to day life; Hackworth gives health advice to his wife and daughters and includes frequent references to religion. Correspondence shows what it was like for Timothy being away from home; Hackworth often communicates how much he misses home and his family, complains of sleeping in damp sheets, lack of clean linen and describes staying in hotels.