Some online collections are available through Tripod. See the History Primary Sources Page for a full listing.
Those that have been edited, reprinted in facsimiles, or transferred to microfilm can be borrowed through E Z Borrow or interlibrary loan if they are not in Tripod. Many of them will be listed in WorldCat under subject terms which include such words as "sources," "letters," "diaries," or "personal narratives." For example, the search china history sources produces results including:
An Anthology of Nineteenth-Century American Science Writing. Edited by C. R. Resetarits.
This collection of primary source documents presents the work of 19th century scientists- all men. In the preface the author includes a paragraph titled "Women and Science" to acknowledge the "limits of this anthology" and point readers toward Rossiter's and Baym's work.