Thermodynamic toys

An overview of the thermodynamic hand boiler, a type of thermodynamic toy, from Xumpscience.
In science toys, thermodynamic toys are those that employ, utilize, or demonstrate noted principles or laws of thermodynamics. Several of these noted historical-based experimental toys are available at, as pictured below.

Galileo thermometer
In 1592, Italian scientist Galileo Galilei invented what most consider the first true thermometer. [1] It was described, according to a retrospect description by Galileo’s friend Benedetto Castelli, many years later, as such: [2]

“Galileo took a glass about the size of a small hen’s egg, fitted to a tube the width of a straw, and about two spans long: he heated the glass bulb in his hands and turned the glass upside down so that the tube dipped in water held in another vessel; as soon as the ball cooled down, the water rose in the tube. This instrument he used to investigate degrees of heat and cold.”

This device seems to have come to have been referred to as a ‘thermoscope’ (a thermometer without a scale), in modern discussion. Galileo’s instrument was said to depend on the observation that air expands when it is hot and contracts when it is cool. The water, differed in respect to mercury in a modern thermometer, serving merely to indicate the expansion or contraction of the air in the bulb. The preliminary heating was a trick to bring the water to a level where it could be seen. [2]

Galileo thermometerGalileo thermometer (close up)

Ball and ring
Left: this Galileo thermometer is 12” tall and contains five 4 degree graduation spheres. Spheres have a small brass plate with a temperature graduation engraved on it. The floating spheres move up and down inside the liquid-filled cylinder depending on the surrounding temperature. The lowest floating sphere in the upper part of the cylinder tells the correct temperature. Right: the ball and ring experimental device explains the principle that molecules and atoms vibrate at higher temperatures and begin to push apart from each other. This phenomenon is known as thermal expansion. Simply heat the brass ball for two minutes. This will cause the ball to expand; hence it will not fit through the ring. When the ball cools down, it will once again fit smoothly through the ring. Great for the classroom or the home laboratory!

In the 1613 words of his student Francesco Sagredo, who used Galileo's device for measuring the difference in temperature between air, snow, and ice, what Galileo had invented was an "an instrument for measuring heat", which can be said to be the first recorded definition of a thermometer. [3] Sagredo used the device to compare the temperature of lakes of different sizes as they cooled in the winter, finding that smaller ones cooled faster than larger ones. He recorded his readings as “degrees of heat”. [4]

Ball and ring
The ball and ring toy (pictured) was originally invented by Dutch physicist Willem Gravesande at Leiden University and demonstrated in his famous circa 1730s ball and ring experiment, which was one of the first experimental measurements or quantifications of the phenomenon volume expansion by heat, which at the time of demonstration was by no means a simply phenomenon to understand nor explain, by virtue of the historical precedence of the various heat element theories (heat element (classical), terra pinguis, phlogiston, and later caloric).

Drinking bird
The drinking bird was invented in the 1940s by American chemist Miles Sullivan, patented by him in 1945, after watching bubbles go up a colored tube on a jukebox machine, and thinking about how much energy was lost by that process
Drinking birdThermodynamic hand boiler
Left: the drinking bird: When the head of the bird is moistened with water it will repeatedly tip over and appear to be drinking from a cup placed in front of it. The dunking is due to the evaporating water, which cools the head reducing the pressure of the gas inside. The liquid inside the bird rises up from his tail towards his head, causing the bird to tip and appear to be drinking. As the bird dunks, the liquid returns to its tail, and the process begins again. In essence this is a small, cleverly designed thermodynamic engine which only needs water to run!Right: the thermodynamic hand boiler: This is a cool, old-fashioned thermodynamic hand boiler toy that is made of hand-blown glass. The liquid inside these beautiful boilers shoots up the tubes and appears to boil when you hold it in your hand. It makes an excellent stocking stuffer for the holidays, or a great classic desk toy for the office setting.

The famous thermodynamic toy the “drinking bird” is an amusing toy, the thermodynamical operation of which was said to have notoriously baffled German-born American physicist Albert Einstein in 1946.

The dipping bird is a loose example of “thermodynamic art”, being a sort of atmospheric heat engine, which will run for days operating on the principle of heat loss via evaporation conjoined with the conversion of heat into work in the working body (liquid-vapor mixture of methylene chloride CH2Cl2) of the engine via the mechanical equivalent of heat. This is similar, in a way, to Greek inventor Hero of Alexandria’s first century AD rotating toy steam engine the "aeolipile", a heat-driven spinning steam ball.

Hand boiler
The thermodynamic hand boiler seems to be a variant of the dipping bird, possibly using liquid-vapor mixture of methylene chloride (CH2Cl2) as the working body (colored liquid). The inventor of this toy needs to be tracked down.

1. (a) Bolton, Henry C. (1900). Evolution of the Thermometer, 1592-1743 (ch. 1: The Open Air-thermometer of Galileo, pgs. 5-24; Ferdinand, pg. 33). Chemical Publishing Co.
(b) Galileo thermometer – Wikipedia.
2. Bailin, David and Love, Alexander. (2004). Cosmology in Gauge Field Theory and String Theory (pg. 21). CRC Press.
3. Muller, Ingo. (2007). A History of Thermodynamics - the Doctrine of Energy and Entropy (ch. 1: Temperature, pgs. 1-7). New York: Springer.
4. McGee, Thomas D. (1988). Principles and Methods of Temperature Measurement (Philo, pg. 3; Fludd, pg. 3-4). Wiley-IEEE.

External links
Thermodynamic hand boiler –
Thermodynamic drinking bird –
Galileo thermometer –
Ball and ring (thermal expansion) –

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