1848-1901

American physicist who designed precise scientific instruments. A civil engineering graduate of Rensselaer Polytechnic Institute, Rowland researched the magnetic behavior of metal. As Johns Hopkins University's first physics professor, he demonstrated that electric charges in motion display magnetism. He refined values for units of electrical resistance and mechanical heat. The ruling engines and concave diffraction gratings he invented enabled scientists to assess an object's physical characteristics more accurately. Rowland won awards for the solar spectrum maps his apparatuses made possible.