What does Jack write about his first experience with thievery in his letter to Henry in Chapter 26?

When Jack is around 6, Silas begins taking him "to school," where he instructs Jack to climb into Buckingham Palace through the chimney and unlock the door so he can steal the King's silver. Jack is interrupted in his letter to discover from Mercy the truth about his being mesmerized - that Tobias, Mr. Butler, and others know he is a convict from New South Wales.