SO long ago as 1653, Sir Hugh Plat, of London, heated glasshouses with steam from a cast–iron pot placed outside. This is described in his book on horticulture, “The Garden of Eden”. James Watt is believed to have used in 1784 the first elementary steam radiator. It was fitted in his study and consisted of an iron box with connecting pipes through which steam was passed from boilers. In 1825, Matthew Murray, of Leeds, the well–known competitor of James Watt, heated his house, which was locally known as “Steam Hall”, by means of exhaust steam from the engine of his adjoining works. Meanwhile, in 1804, Oliver Evans in the United States had mentioned in one of his patents the use of exhaust steam from engines for heating.