Thomas Seavey Hall
Born April 1, 1827 – December 1, 1880
Improvement in Electric Signals
Patent #: 89,308
The 1860s and 1870s were pivotal decades for improving the safety in the
railroad industry. Many of these innovations were invented by Thomas Hall.
Born in Upper Bartlett, New Hampshire, Hall attended Middlebury College. In 1886, he witnessed a train accident that occurred from a misplaced switch. In response, Hall set out to invent improved signals that would better alert train engineers to the presence of oncoming trains as well as alerting travelers crossing railroad intersections. His first patent was designed to alert employees of station homes to an improperly placed switch. The system was designed to produce an alarm that would sound continuously in case a switch was not properly placed.