Does using an instrument make you mathematical? Mathematical practitioners of the 17th century

Gaining an insight into what it meant to be a mathematical practitioner in the 17th century is difficult. People who thought themselves mathematical included navigators, sundial makers and book-keepers. For some, the simple use of instruments was construed as mathematical; for others, this was merely a 'showing of tricks'. One profession reliant on mathematics was land surveying. An analysis of this profession throws up many interesting questions about what it meant to be mathematical in early modern England.