For a wide contextual look at Singer machines and the firm in general,
see David Hounshell's FROM AMERICAN SYSTEM TO MASS PRODUCTION.  Hounshell
discusses Singer's quest for interchangeability, and the book has an
interesting material culture bent to complement its focus on the history
of technology.  See the photos near the end of the book for things to
look for in Singer machines.

Hope this helps.

Regards,
Doug

........................
Doug Lantry
University of Delaware
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