Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

By the time of his death in 1878, Joseph Henry was America's most eminent physical scientist. His achievements in the study of electricity, magnetism, and telegraphy earned him a 30-year tenure as the first secretary of the Smithsonian. This biography illuminates not only the character of 19th-century scientific exploration but also the place of science in American culture. 12 illustrations.

Reprint of the original, first published in 1880.