Patents -- United States

The papers in the Boone-O'Brien-Harnickell collection span a period from 1878 until 1974, with the bulk of these falling between the years 1939 and 1950. The majority of the papers are letters, documents and cards, although there are a few hand-written manuscripts.

This collection gives a good sampling of the wide ranging interests of William A. Crawford-Frost, from philosophical speculation to inventing. One box contains correspondence, patents, and misc. notes and items; the next four boxes contain copies of his writings, some in handwritten drafts, some typescript, some mimeographed and some printed

This collection contains the personal financial journals of Henry Clay Preston, 1917-1957 (3 volumes). The collection also includes Clay's marriage certificate and patents for machine tools invented or improvements by Preston.

This collection contains patents to various Fredrick and Prince Georges County properties purchased by Thomas and Nathan Maynard from 1735-1790. Also included are genealogical notes on the Maynard family, "Securities" and "Belongings" lists, 1921, of Eleanor Maynard, as well as Ms. Maynard's will, 1918.