
author
1848–1901
A pioneering American physicist, he helped turn precision measurement and spectrum analysis into powerful tools for modern science. His work on diffraction gratings and his long career at Johns Hopkins made him one of the most respected experimental physicists of his era.

by Henry Augustus Rowland
Born in Honesdale, Pennsylvania, in 1848, Henry Augustus Rowland became one of the leading American physicists of the late nineteenth century. He joined the newly founded Johns Hopkins University in 1876 as its first professor of physics and remained there for the rest of his life.
Rowland is best remembered for his work on diffraction gratings, especially the concave grating that greatly improved the study of light spectra. He also carried out important research in electricity and magnetism, and his skill as an experimental scientist gave him an international reputation.
Beyond his research, he helped shape American physics as a profession. He served as the first president of the American Physical Society from 1899 until his death in Baltimore in 1901.