Later applications included the blast furnace process known as hot blast and the open hearth furnace also called Siemens regenerative furnace (which was used for making glass), where the hot exhaust gases from combustion are passed through firebrick regenerative chambers, which are thus heated.
This led to later applications of the blast furnace process known as hot blast and the open hearth furnace also referred to as the Siemens regenerative furnace (used in glass production), where hot exhaust gases from combustion are circulated through heated chambers.