Mayer has also been styled the discoverer of the fact that heat consists in (the energy of) motion, a matter settled at the very end of the 18th century by Count Rumford and Sir H.
For the next twelve years (passed chiefly in London or at Largo, with an occasional visit to the continent of Europe) he continued his physical studies, which resulted in numerous papers contributed by him to Nicholson's Philosophical Journal, and in the publication (1804) of the Experimental Inquiry into the Nature .and Properties of Heat, a work which gained him the Rumford Medal of the Royal Society of London.
He was also the founder of the Rumford medal of the American Academy of Arts and Sciences, and of the Rumford professorship in Harvard University.
Sabine remarked when awarding him the Rumford medal of the Royal Society in 1872, contains a fundamental principle of spectrum analysis, and though for a number of years it was overlooked it entitles him to rank as one of the founders of spectroscopy.
Since one horse was capable of doing the work required, Rumford remarked that one horse can generate heat as rapidly as nine wax candles burning in the ordinary manner.
Rumford was the founder and the first recipient of the Rumford medal of the Royal Society.
The earliest experiments of this nature are due to Benjamin Robins in 1743 and Count Rumford in 1792; and their method has been revived by Dr Kellner, War Department chemist, who 5 employed the steel spheres of bicycle ball-bearings as safetyvalves, loaded to register the pressure at which the powdergas will blow off, and thereby check the indications of the crusher-gauge (Proc. R.S., March 1895).
In 1800, and Rumford himself selected Sir Humphry Davy as scientific lecturer there.
He was awarded the Janssen medal by the Paris Academy of Sciences in 1894, the Rumford medal by the American Academy in 1902, the Draper medal in 1903, a gold medal by the Royal Astronomical Society in 1904, the Bruce medal by the Astronomical Society of the Pacific in 1916, and the Janssen medal by the Astronomical Society of France in 1917.
Lockyer was elected a fellow of the Royal Society in 1869, and received the Rumford medal in 1874.