Potential means of cost reduction in grade crossing automatic gate systems. Volume II: improved gate arm concepts for railroad/highway grade crossings. Final report.

Transportation Systems Center, Cambridge, Mass.

Volume of Arm in relation to Circulation and Respiration

Alice Hamilton (standing) in physiological laboratory (source: Not Just Any Medical School by Horace W. Davenport) Plethysmographic measurements of the forearm as described by Sewall and Sanford ... (source: Physiology at Michigan, 1850-1923)