This film is part of Free

Circulation
Let it bleed? This exemplary education film gets to the heart of the matter.
Overview
This admirably clear explanation of the mechanics of blood circulation showcases the art of educational filmmaking in its 1930s golden age. Its blend of simple animation, models and lab set-ups (including an artificially beating rabbit's heart) effectively illustrates the functioning of the heart, the role of arteries, veins and capillaries in regulating blood flow and the way valves prevent blood travelling backwards through the veins. The film has aged well, too – were it not for the black and white photography and the inevitably plummy narration it could easily be mistaken an Open University production from decades later.
The 1930s was the golden age of the educational film in Britain, and Gaumont-British Instructional was its most prolific exponent. This was the final part of a three-part series, Hygiene, for GBI, with all three directed by Donald Carter and supervised by Professor Winifred Cullis, the first woman to hold that position in a British medical school.
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