Orson Squire Fowler (1809 – 1887) was a phrenologist and lecturer. He also popularized the octagon house in the middle of the nineteenth century.
Fowler wrote and lectured on phrenology, preservation of health, popular education and social reform from 1834 to 1887 and was largely responsible for the mid-19th century popularity of phrenology, the pseudoscience of defining an individual's characteristics by the contours of the head.
https://en.wikipedia.org/wiki/Orson_Squire_Fowler
Fowler made his mark on American architecture when he touted the advantages of octagonal homes over rectangular and square structures in his widely publicized book, The Octagon House: A Home For All, or A New, Cheap, Convenient, and Superior Mode of Building, (1840). Octagon houses were a unique house style briefly popular in the 1850s in the United States and Canada. They are characterised by an octagonal (eight-sided) plan, and often feature a flat roof and a veranda all round.
https://en.wikipedia.org/wiki/Octagon_house
The Octagon House, in Danbury, Connecticut is considered the best octagon house of the 12 that survive in Connecticut. In 1973 it was added to the National Register of Historic Places to avert its demolition in urban renewal.
https://en.wikipedia.org/wiki/Octagon_House_%28Danbury,_Connecticut%29
http://www.octagon.bobanna.com/CT.html
On July 8, 2015, the City of Danbury announce dplans to acquire the house and to use it for the city's specialblight-fighting Unified Neighborhood Inspection Team.
http://www.newstimes.com/news/article/Danbury-to-rescue-historic-Octagon-House-from-ruin-6371045.php