Born into a Quaker family in Barnesville, Ohio, Gray was brought up on a farm. He spent several years at Oberlin College where he experimented with electrical devices. Oberlin is a town southwest of Cleveland, Ohio. Although Gray was not a graduate of Oberlin College, he taught electricity and science at Oberlin and built laboratory equipment for Oberlin science departments.
In 1862 while at Oberlin, Gray met and married Delia Shepard.
In 1865 Gray invented a self-adjusting telegraph relay that automatically adapted to varying insulation of the telegraph line.
In 1867 Gray received a patent for the self-adjusting telegraph relay and in later years he received patents for more than 70 other inventions.
See Elisha Gray's patent caveat and drawings of his new invention, the telephone.