This study began as an attempt to understand mechanics in the nineteenth century. The terms
mechanics and mechanical world view were being used as general descriptions of
nineteenth-century physicists' assumptions and interpretations of nature. However there were
no studies of the particulars of these assumptions or the range and content of these
interpretations. Rene Dugas' work on classical mechanics focused on France. The search for the
particulars of these forms of mechanics led me to explore precisely what mechanics meant to
physicists of a century and more ago. However none of Lagrange's Hamilton's or Jacobi's
mechanics while ele gant fits easily within the history of physics. Lagrange reduced
mechanics to an exercise in analysis Hamilton and Jacobi used mechanics to explore solutions
to partial differential equations. They were mathematicians doing mathematics. As I went deeper
into the matter it became obvious that in the nineteenth century there were two kinds of
mechanics each containing a variety of forms one physical the other mathematical. There were
a group of men using mechanics to understand nature and another group using the equations of
mechanics to explore the calcu lus. However when tracing these two traditions back into the
eighteenth century physics disappeared altogether.
