Amos Dolbear was born in Norwich, Connecticut, on November 10, 1837. He was orphaned at the age of four and was taken to Roxbury, New Hampshire, to live with Deacon Moses Guild. Dolbear attended the one room district school in Roxbury and was noted as a quiet and studious youngster. He later left Roxbury and worked his way through college as a school teacher. Dolbear graduated from Wesleyan University of Michigan the following year. He soon became professor of natural sciences at Bethany College in West Virginia. In addition to teaching, Dolbear served two terms as mayor of the city of Bethany. In 1874 he took a job as professor of physics and astronomy at Tufts College, where he was affectionately known to the students as 'Dolly'.
While a student at Ohio Wesleyan, he had made a 'talking telegraph' and invented a receiver containing two features of the modern telephone; a permanent magnet and a metallic diaphragm that he made of a tintype. He invented the first telephone receiver with a permanent magnet in 1865, 11 years before Alexander Graham Bell patented his model. Later, Dolbear couldn't prove his claim, so Bell kept the patent after a court hearing in 1881.
In 1882 Professor Dolbear was able to communicate over a distance of a quarter of a mile without wires in the Earth. It is interesting to note that the Tufts Professor was ahead of Hertz and Marconi. He received a U.S. patent for a wireless telegraph in March of that year. His device relied on conduction in the ground, a type of radio transmission. His system used phones grounded by metal rods pushed into the earth. His transmission range was at least as much as a half a mile. He received a patent for this device in 1886. More importantly the Dolbear patent prevented the Marconi Company from operating in the United States. In the end Marconi had to purchase Dolbear's patent, primarily because it was similar to the 1896 model of Guglielmo Marconi and because it was tractable in specific applications (such as transmission in the earth).
He died on February 23, 1910, aged seventy-three. He will probably be most remembered for an article he published in 1897, "The Cricket as a Thermometer". In that article he noted the correlation between the ambient temperature and the rate at which crickets chirp. The formula expressed in that article became known as Dolbear's Law.