Tyndall’s ice flowers

This 1930s black and white silent film shows the setting up of an experiment using a magic lantern as a light source, water tank and a block of ice.

This early teaching film is recreating some of the early experiments carried out by John Tyndall at the Royal Institution.

John Tyndall was a prominent 19th century physicist and keen mountaineer. While undertaking his researches into diamagnetism he also applied his scientific knowledge to other problems, including the structure and motion of glaciers. During his researches he observed how ice was formed and how it melted.

Tyndall’s ice flowers refers to the small water-filled cavities, often of basically hexagonal shape, which appear in the interior of ice masses upon which light is falling. This patterning occurs when the light causes the surface and the interior to melt.

This short film shows what happens when a piece of natural ice is placed in the beam of a lantern. The heat carried in the beam is first absorbed by a small glass-sided tank filled with water. When the small tank is removed from the beam, the heat reaches the ice, in the interior of which it is absorbed. The ice melts within, as well as on the surface. The crystalline forms, which built up the block during freezing, become evident as the process is reversed; the absorbed heat breaking down the structure, crystal by crystal, leaving water in the shape of the separate melting crystals.

Ice floats on water, so when an ice crystal melts, the water it forms as the ice flower grows occupies a smaller space, leaving a little bubble, which can be seen growing and moving about in each ‘flower’ as it spreads out.

This is a Kodak Ltd ‘Cine-Kodagraph’ film most likely filmed in the basement laboratories of the Ri where the structure of ice was determined through X-ray crystallography.

For this film, and several others in our collection, we have tried to contact any known copyright holders and believe it to be an orphan work. If you are the rights holder, would like it to be taken down, or have any more information, please get in touch at richannel@ri.ac.uk.

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