Physical Sciences/Math
CalTech Archives includes manuscripts, notebooks http://caltechln.library.caltech.edu/, photographs, oral historieshttp://oralhistories.library.caltech.edu/ of astronomers, physicists and technologists
Newton Papers (Cambridge Digital Library) offers Newton's manuscripts
The Newton Project – Includes all of Sir Isaac Newton's writings (printed or not), with translations, and also includes the listing of books in Newton's library.
Archimedes Project- an ongoing. multi-institution effort to digitize historic writings in the history of mechanics and engineering from antiquity to the Renaissance to help scholars mine myriad scientific texts in a variety of language and connect the dots between them.
Boyle Papers Online: Birkbeck, University of London - Images of the core volumes of the papers of Robert Boyle, considered one of the founders of modern science
The Workdiaries of Robert Boyle: The Centre for Editing Lives and Letters - written between 1647 and 1691, they provide a vivid record of observation and experimentation by one of founding fathers of modern science
Newton Papers- largest collection of the scientific works of Isaac Newton (of physics, gravity and calculus fame).
Galileo:
The Galileo Project-- the life and work of Galileo. Includes English translation of letters from Maria Celeste Galileo to her father (the primary sources used for the 1999 book Galileo's Daughter by Dava Sobel).
Museo Galileo vast collection including both research content and online exhibitions, from manuscripts to scientific instruments.
Mathematics
Mathematics Genealogy Project includes dissertation titles, universities and advisors for over 28,000 mathematicians worldwide, 1796 - . Plan is to include all 20th century mathematicians.
Eugene B. Dynkin Collection of Mathematics Interviews (Cornell)
Numdam, the French digital mathematics library
Historical Math Monographs (Cornell).
DML: Digital Mathematics Library (Also: WDML: World Digital Mathematics Library): Retrodigitized Mathematics Journals and Monographs
Astronomy
NASA Astrophysics Data System (Harvard login)
Observatory and other astronomical serial publications
Linda Hall Library Digital Collections Astronomy
NASA History --Find historical documents from NASA, including press releases, mission transcripts, and speeches.
Eisenhower Library: The Early History and Development of the National Aeronautics and Space Administration (NASA) --Browse documents related to the creation of NASA, including press conference transcripts, cabinet meeting minutes, memorandums, and letters
Physics
American Institute of Physics Digital Archive includes digitized archival material and many oral histories.
Digital Collections Color and Optics (Linda Hall Library) (17th-20th centuries) -- works on scientific theories of color and industrial applications.
Collected Papers of Albert Einstein
Wellcome Collection includes works on optics.
International Nuclear Information System (INIS) (1956- ).
Museum of Radiation and Radioactivity (Oak Ridge Associated Universities)
Health Physics Historical Instrumentation Museum (Oak Ridge Associated Universities)
Chemistry and Alchemy
Chemical Genealogy Database. Entries include chemist, their teacher, students, and those known to have influenced them or have been influenced by them.
RSC Gold (1876- ) offers Royal Society of Chemistry Journals
Selected Classic Papers from the History of Chemistry
Panopticon Lavoisier - Virtual museum of the works of Antoine Laurent Lavoisier (1743-1794), including digitized manuscripts, laboratory apparatus, library, bibliography, iconography.
Database of Alchemical Manuscripts
Edgar Fahs Smith Collection offers images of scientists, apparatus and laboratories illustrating pre-1850 chemistry
Industry Documents Library (UC San Francisco) Includes: Chemical Collections