English engineer and inventor of the surface condenser for steam boilers.

The son of a cotton manufacturer, in 1817 Hall devised a method for removing loose fibres from lace by passing the fabric swiftly through a row of gas flames. His process was widely adopted and earned him a fortune, much of which he lost on other inventions.

In subsequent years Hall attempted to find a means by which steamships could charge their boilers with fresh water at the beginning of their voyage and use it over and over again, so as to avoid the use of corrosive salt water. In 1838 he patented a surface condenser in which the steam passed through a number of small condensing tubes cooled on the outside. Although his invention received extensive trials in 1839–41, it proved unsuccessful. The principle of the tubular condenser survived, however, and is now used mostly in cooling devices. Hall held more than 20 patents, mostly for devices relating to steam engines and boilers.