This series consists of records created or gathered in the course of John Wesley Hackworth’s business actitvities after the death of his father. Some such as specifications appear to have been gathered retrospectively by him as they occour too early for him to have been involved.

The majority of records in this series relate to John Wesley Hackworth inventions, for example specifications patents. The series also contains agreements that are evidence of John Wesley Hackworth’s business relationships. The series also contains specifications in the name of other parties, such as David Joy who John Wesley Hackworth challenged for infringing his own patent that was brought out in America.