This small notebook records the dates and exact times of the births of seven of the eight children James, Duke of York (later James II) had with Anne Hyde, and his first three children with Mary of Modena. Poignantly, the early deaths of most of his children are also recorded. It is unclear who compiled the list, but the notebook was probably designed for James, whose distinctive 'JD' (James Duke) monogram appears on the elaborate binding. The book seems to have been written at one sitting in late 1677, early 1678.

In March 1671 Anne Hyde died. Facing the page recording this is a lock of hair – presumably hers. The next entry is for James's second marriage: 'The Duke was Mar[ried] & Bedded at Dover to ye Princes[s] Mary of Modena on Fryday ye 21st of Nov[ember] 1673'.