He liked to invent or plan mathematical puzzles and solving what others brought him to solve. Benjamin constructed a striking wall clock without ever seeing one. He made the clock by visualizing a mathematical puzzle. He related the toothed wheels and gears to a poxket knife. The clock worked for more thean fifty years until he passed away. Benjamin inherited the family farm after his father passed away so he continued selling tobacco until he was 59 years old. He also assisted Andrew Ellicott who was selected by President George Washington to produce a survey of selected lands which established a national capital. Andrew needed an assistant who knew astronomy but he chose his cousin but his cousin was unable to leave his own job so he recommended Benjamin. So Andrew hired Benjamin. Benjamin worked in the observatory tent for more than 4 months. He was there from the beginning of February until the end of April