Collections : [University of Michigan William L. Clements Library]

Leo Engleman worked trigonometric and surveying exercises in this cypher book from 1847 to 1848, possibly while a thirteen-year-old boy living in Pennsylvania. Many of the exercises include mathematical drawings and illustrations, and surveying examples often include additional features done in pencil and watercolor.

Leo Engleman worked trigonometric and surveying exercises in this cypher book from 1847 to 1848, possibly while a thirteen-year-old boy living in Pennsylvania. Many of the exercises include mathematical drawings and illustrations, and surveying examples often include additional features done in pencil and watercolor, such as trees, rivers, buildings, and lighthouses. A number of headings also feature watercolor embellishments and abstract or geometric designs, and the final pages of the volume include full-page watercolor designs of geometric shapes and a rose bush.