One handwritten manuscript and one typescript intended for speeches presented by Charles F. Brush, Sr., no date. Handwritten manuscript for a speech g Show moreOne handwritten manuscript and one typescript intended for speeches presented by Charles F. Brush, Sr., no date. Handwritten manuscript for a speech given by Charles F., Sr. transmitted to a separate audience, no date. Brush discusses the definition of electricity, corpuscles and negative electricity, and concedes that at least negative electricity may be considered a form of matter, not a phenomenon of the ether. Typescript for speech given by Charles F., Sr. entitled, Transportation of Air at Low Pressures, no date. Brush discusses his experiments and conclusions related to Grahams law of transpiration as it applies to air at low pressures Charles F. Brush, Sr., Papers Series 8: Other Papers (1842-1960) Subseries 4: Miscellaneous (1842-1960) Box 29 Folder 7 Show less