Via Washington University, St Louis’ Biology Library News, I read that the National Academy of Sciences has made its entire historical collection of biographical memoirs freely available online, as PDFs. Fom the National Academy website:

Published since 1877, Biographical Memoirs are brief biographies of deceased National Academy of Sciences members, written by those who knew them or their work. These biographies provide a personal and scholarly view of the lives and work of America’s most distinguished scientists and a biographical history of science in the United States.

Over the next several months, the entire collection of Biographical Memoirs will be available online as PDFs. Although memoirs published since 1995 have been freely available online, more than 900 memoirs published prior to 1995 were available previously only through archives and libraries. Among the 500 memoirs published recently online are those of famed naturalist Louis Agassiz; Joseph Henry, the first secretary of the Smithsonian Institution; Thomas Edison; Alexander Graham Bell; noted anthropologist Margaret Mead; and psychologist and philosopher John Dewey.

The alphabetical list of available memoirs is at this link. You can also sign up to an email list to receive news of updates.