Diary of a traveler from Vienna, Austria, with the surname Rehn to the United States in 1869. The author describes his travel to cities in the Middle Atlantic and Midwest regions--Washington, Philadelphia, New York, Pittsburgh, Cincinnati, Cleveland, and Chicago. He comments on the technology (factories, machines, railways, etc.) and architecture (bridges, buildings, social facilities, etc.) he sees. The diary contains a variety of sketches, including sketches of buildings, floor diagrams, bridges, etc. Also included are a travel diary for a trip to Italy in 1875; four engravings of Viennese buildings, 1856-1875; and two geological maps, 1866-1873. In German.

After a brief career in the Congregational church, J. Peter Lesley (1819-1903) left the ministry in 1852 to work full-time as a geologist. Having gained experience in structural geology and stratigraphy with the First Pennsylvania Geological Survey (1836-1842), Lesley became an expert in the geology of coal, working for the Pennsylvania Railroad and other corporations and conducting some of the first systematic studies of the state's hydrocarbon resources. A long-time professor at the University of Pennsylvania, he was elected to the APS in 1856, serving variously as its librarian, secretary, and vice president, and he was selected as Director of the Second Pennsylvania Geological Survey (1875-1889). The Lesley Papers include letters to and from Peter Lesley and his wife, Susan on geology, coal and iron mining, abolition, educational reform, organized charity, and Unitarianism. The collection offers important insight into academic and applied geology in late 19th century Pennsylvania, the development of the coal and iron industries, as well as into the Lesleys' progressive social and intellectual milieu. It is divided into three series: Lesley's general correspondence, his correspondence with his brother Joseph, and microfilms of Lesley's research notes.