The title reminds of two early heroes of what we know today as thermodynamics. More precisely, the first law of thermodynamics. First I must acknowledge that I only heard about them due to the excellent formation in physics I had at the Instituto de Física da Universidade de Sao Paulo.
Benjamin Thompson was a curious fellow. Born in the United States (better said, in the Massachussets colony), he fought in the American Independence War (at the side of the British), made career in the British Empire (was raised to knighthood) and later went to work for the King of Bavaria (from where his noble title stems, apparently). In other words, he was a sort of a mercenary.
Benjamin Thompson, 1753 – 1814 (source: wikipedia)
His famous discovery was made while drilling holes in bronze to produce cannons. Everyone who already did this (drill holes in any metal) will agree that the metal piece becomes quite hot. At that time people believed heat was a kind of fluid (a liquid called caloricum) which could be shared by different bodies by flowing.
Thomson devised an experiment to disprove this notion. He placed the drill and the cannon inside water and showed that the water could be brought to boil just by the drilling activity. More than this, he showed that the amount of available heat was practically infinite, depending only on the work done by the drilling activity, and showed that no transformation happened in the material, by comparing the specific heat of the removed material (metal chips) with that of the bronze piece.
He correctly stated, based on this experiment, that mechanical work could be transformed into heat by friction, and it seems that he had the notion that their sum must be conserved, but this was not stated in his work.
Robert Meyer, on the other hand, was a German. He is described in the modern texts as a physician (meaning medic), but one has to remind that at this time all of them were polymaths, so these distinctions we have today made no sense.
Robert Meyer, 1814 – 1878 (source: Hmolpedia)
His key experiment was an observation. Working as ship physician in the coast of Java, he noticed that the venous blood of the sailors was less dark than the color he was used to in Germany. This blood was mostly red and only slightly darker than the arterial blood. He correctly assumed that this was a consequence of the different average temperatures in both places, arguing that the body heat is generated by combustion and that more combustion is needed in the cold Germany compared with the hot Java. He also observed (or better, was told by the sailors), that the sea water heated after a storm, and that this was due to agitation (mechanical work). Later he did experiments and came out with a value for the R constant (the mechanical equivalent to heat), and correctly stated the conservation of the sum of heat and mechanical work (the first law). He also published a small brochure in 1851 correctly stating that mechanical work and heat could be transformed into each other.
He tried to publish his findings in the Ann. Chem. Phys. in 1841 (two years before Joule) but was ignored. With help of friends he managed to publish a work in the Annals of Chemistry and Pharmacy in 1842. It seems that the problem was that he used philosophical ideas (principally by Immanuel Kant) to justify his physics, bordering metaphysics. His role in thermodynamics was acknowledged only after Helmholtz lectured about him to a group of physicist.
Both characters were complicated persons. Thompson is remembered for his correct interpretation of the drilling experiment, but he also defended very weird theories which were later proven wrong. Meyer was an adept of philosophical thought and obviously designed and interpreted his experiments in the light of these theories (i.e. by preconception), what is today considered frontally wrong in the scientific method. Meyer was also one of Boltzmann’s antagonists, equating his ideas with alchemy (an intended insult, of course).
The important is to realize, however, that both characters relied on observation of physical phenomena to reach their conclusions, something which was very alive in the birth years of thermodynamics, but has been forgotten since then.
I always remind my students not to judge past characters using present day’s moral compass. Thompson and Meyer are products of their respective times and what is contradictory today made perfect sense to them at that time. Their role in the development of thermodynamics, in particular, of the first law, cannot and should not be overlooked.
On Thompson: https://en.wikipedia.org/wiki/Benjamin_Thompson
On Meyer: http://www.eoht.info/page/Robert+Mayer