Example image of eyePlorer eyePlorer map for 'Joseph Henry': Smithsonian Institution United States Benjamin Franklin Electromagnetism Michael Faraday Henry (unit) International System of Units Charles Wheatstone Electrical telegraph Samuel Morse Albany, New York Galway (village), New York Silversmith Watchmaker The Albany Academy Hudson River Lake Erie Surveying Civil engineering Mechanical engineering Theodric Romeyn Beck Earth's magnetic field Magnetism Electromagnet William Sturgeon Yale University Electrode Electric motor Stephen Alexander (astronomer) Sunspot Thermopile Angelo Secchi Jet stream Thaddeus S. C. Lowe Medford, New York Philadelphia Cincinnati Confederate States of America Simon Cameron Union Army Balloon Corps Room acoustics University of Göttingen Alexander Graham Bell Philosophical Society of Washington Georgetown, Washington, D.C. Oak Hill Cemetery (Washington, D.C.) United States Lighthouse Board United States Coast Guard Hall of Fame for Great Americans Relay