Close-ups of the Helmholtz Double Siren скачать в хорошем качестве

Close-ups of the Helmholtz Double Siren

The Helmholtz Double Siren is from the Koenig collection of historic acoustic instruments in the University of Toronto Scientific Instrument Collection. Rudolph Koenig was a master instrument maker based in Paris. The Toronto Koenig instruments were purchased in 1878 by Professor James Loudon to build the first laboratory of physics in Canada. They had previously been shown at the Philadelphia exhibition in 1876. The double siren consists of two Dove sirens on a common shaft, facing one another. A series of stops allow different sets of holes, and hence different notes, to be selected. The phase difference between the upper and lower siren can be adjusted by rotating the upper siren. Here, the siren is being operated by David Pantalony, curator of Scientific Instruments at the Canada Museum of Science and Technology, Ottawa during his visit to Toronto on January 18, 2013. Filmed by Prof. Stephen Morris Department of Physics.