Sir James Chalmers (1828–1901) was a Scottish accountant and courtier. He is not to be confused with his father, also named James Chalmers (1782–1853), who was a bookseller and printer credited as an early pioneer of the adhesive postage stamp.
If you’d like, I can also explain how the role of Keeper of the Privy Purse differs from that of the Private Secretary today, or provide a timeline of key holders.