Calorus: Caloric Theory of Heat
Thermodynamics & Statistical Physics arc, page 59 of 193. Back to The Pixelated Physics Universe
Who they are
Calorus, a bronze-armoured knight with a sealed glass chest-plate of glowing fluid, is pierced by a blunt borer; from the wound pours heat-shimmer, not fluid, and the vessel stays full.
Calorus is a character of the Thermodynamics & Statistical Physics arc: drawn in pixels, ruled by one piece of real physics, and never allowed to break it.
The physics
Antoine Lavoisier’s Traité élémentaire de chimie (1789) listed caloric, a conserved, weightless heat fluid, among the elements. In 1798 Count Rumford reported that boring a cannon with a blunt borer kept producing heat seemingly without limit, enough to boil water in about two and a half hours, and argued that heat is a form of motion. The fluid picture faded around 1850, when J. P. Joule’s “On the mechanical equivalent of heat” and Rudolf Clausius’s founding paper of thermodynamics made heat a transfer of energy, not a substance.ΔU = Q − WJoule 1850: 772 ft·lbf per Btu ≈ 4.15 J per calorie (modern: 1 calth = 4.184 J exactly) ΔU: change in a system’s internal energy (J) Q: heat added to the system (J) W: work done by the system (J) ft·lbf: foot-pound-force, ≈ 1.356 J Btu: heat to warm one pound of water by 1 °F, ≈ 1055 J calth: thermochemical calorie (J) The first law says heat and work are two ways of moving the same energy, so there is no stock of caloric to run out of, and none to conserve. Rumford’s borer converted mechanical work W into internal energy indefinitely.
No single equation is shown for this character; the physics above is stated in words because it is an observation or a piece of history, and we do not invent formulas.
Honest caveat: Heat-fluid ideas are older than 1789; Lavoisier named and listed caloric. Rumford’s result was not accepted as decisive at the time, and 1850 is a conventional end date, marked by Joule’s and Clausius’s 1850 papers; caloric theory faded gradually.In characterThey pierced me and waited for me to drain. I never did. Whatever pours out of me is motion, and the more they bore, the more I give.
Crossovers
Calorus meets Endoreva (Curzon Ahlborn Efficiency). Calorus thought heat was a conserved fluid. Endoreva's engine turns part of the heat into work, which is exactly what the caloric fluid could not allow. Heat is energy in transit, not a substance.
Calorus meets Kelvinor (Kelvin's Age of the Earth). Calorus's heat-as-fluid was overturned by work turning into heat. Kelvinor, a founder of the new thermodynamics, used heat conduction to estimate the Earth's age. He got the physics of conduction right, but his age was wrong because he left out heat sources.
Wear the lore
Concept keywords: Caloric Theory of Heat, Calorus, Thermodynamics & Statistical Physics, physics lore, Pixelated Physics