Jeremiah Head worked at Robert Stephenson and Co (RS&CO) for five years from the age of 16 (1852 – 1857). He served three and a half years in the pattern-making, fitting, and erecting shops and the remaining year and a half in the drawing office, the diary covers the drawing office period.

The diary details a variety of Head's projects for Robert Stephenson & Co, including locomotive projects: ‘At R.S. & Co's we have just got an order for 50 locomotives for the Lombardo-Venetian line’ it also covers the design of regulators and steam mills.

During the period Head was writing his diary he worked on the design and build of two compound mill engines for Henry Pease and Co and Annandale and Sons; worked to reconstruct Rowland Burden’s cast iron bridge over the River Wear; and designed a steam plough based on an idea conceived by John Fowler, who is mentioned numerous times in the diary.

The diary documents meetings and social events with prominent railway individuals including Robert Stephenson. He met Edward Pease (1767-1858), woollen manufacturer and railway promoter, "By & bye old Neddy came in, shook my hand & said he had often wanted to see me. He is a remarkably fine pleasant well-informed old man 90 years old & as brisk as most men of 70. He talked a deal about the Stephensons &c... I was delighted to have made the acquaintance of a man so celebrated in the history of railways".

The diary includes personal information about Head’s health, social events, railway travel and other personal comments. There is a detailed family tree (loose) in the front of the diary.