According to
http://www.sil.si.edu/DigitalCollect...g-machines.pdf
page 22 says that it was formerly the New York Sewing Machine Company from 1880-1882 and Demorest Manufacturing Company from 1882-1908
See also:
http://www.sil.si.edu/DigitalCollect...0811/index.htm
http://www.sil.si.edu/DigitalCollect...0807/index.htm
Have you tried Google site specific searches? - such as (use each line as a search term)
demorest site:needlebar.org
demorest site:ismacs.net
demorest site:quiltingboard.com
Janey - Neat people never make the exciting discoveries I do.