There's a few good sites:
http://outreach.atnf.csiro.au/educat...tro_types.html
http://www.peripatus.gen.nz/astronomy/wolraysta.html
The astronomical Spectroscopy Y! group had some other good links:
http://tech.groups.yahoo.com/group/a...guid=322612425
Then there is the Gutenberg ebooks:
The following books are also available on the web for download at
www.archive.org . They give a wonderful insight into the early years of spectroscopic development.
- “The Spectroscope and its work” – Richard A Proctor, 1888
- “The Spectroscope and its applications” – J Norman Lockyer, 1873
- “How to work with the Spectroscope” – John Browning, 1882
- “Sir William Higgins and Spectroscopic Astronomy” – E W Maunder, 1913