Morse's interest in electricity, aroused in his college days, was further stimulated by the lectures of James F. Dana in 1827 and later by contacts with university faculty. Learning in 1832 of Ampère's idea for the electric telegraph, Morse worked for the next 12 years, with the aid of the chemist Leonard Gale, physicist Joseph Henry, and machinist Alfred Vail to perfect his own version of the instrument. So many phases of the telegraph, however, had already been anticipated by other inventors, especially in Great Britain, Germany, and France, that Morse's originality as the inventor of telegraphy has been questioned; even the Morse code did not differ greatly from earlier codes, including the semaphore. In any case, in 1844 Morse demonstrated to Congress the practicability of his instrument by transmitting the famous message "What hath God wrought" over a wire from Washington to Baltimore. Morse subsequently was compelled to defend his invention in court, although by then he commanded the acclaim of the world. He later experimented with submarine cable telegraphy. Both Morse and John Draper were instrumental in introducing the daguerreotype in the United States.
See his letters and journals, ed. by E. L. Morse (1914, repr. 1973); biographies by C. Mabee (1943, repr. 1969), P. Staiti (1989), and K. Silverman (2003).
It is likely that Samuel Finley was a graduate of William Tennant's Log College, in Neshaminy, Bucks County, Pennsylvania, known for its training of evangelical Presbyterian ministers who played a role in the 18th Century religious revival known as The Great Awakening. Finley also was awarded an honorary degree by the University of Glasgow.
On September 26, 1744 Samuel Finley married Sarah Hall (1728- July 30, 1760), daughter of Joseph Hall and Rebecca Rutter. Various sources report five sons and three daughters were born of this union. On May 13, 1761, he married Ann Clarkson (1730-1807), daughter of Matthew Clarkson and Cornelia de Peyste, of Philadelphia. They reportly had issue.
Finley's first wife, Sarah Hall, was the sister of Susanna Hall Harvey, the mother of Dr. Benjamin Rush, a signer of the Declaration of Independence. Benjamin Rush moved into the Finley home at the age of six (some sources say eight) upon the death of his father, and was one of Finley's students at West Nottingham Academy. Finley is said to have convinced Rush to become a physician. Rush later attended Finley as Finley's physician at the time of Finley's death.
Another signer of the Declaration of Independence, Richard Stockton, studied under Rev. Finley at West Nottingham Academy. Stockton's daughter, Julia, subsequently married Benjamin Rush.
During Finley's five year presidency at Princeton, the college graduated 130 students, including the Rev. James Manning (graduated in 1762), the founder and first president of Brown University; Ebenezer Hazard (1762), the third United States Postmaster General; William Paterson (1763), the second governor of the State of New Jersey; the Rev. Samuel Kirkland (1765), founder and first president of Hamilton College; David Ramsay (1765), physician and historian of the American Revolution; and Oliver Ellsworth (1766), the third Chief Justice of the United States. Finley's sermons, Hazard said: "were calculated to inform the ignorant, to alarm the careless and secure, and to edify and comfort the faithful".
Genealogical and Personal History of Fayette County Pennsylvania, Vol. I-II, John W. Jordan, ed. New York, USA: Lewis Historical Publishing Company, 1912