cloud chamber
Date1934-1935
Inventory Number1998-1-0050
ClassificationCloud Chamber
Subject
Maker
Jabez Curry Street
1906 - 1989
Maker
Edward C. Stevenson
User
Lyman Laboratory of Physics, Harvard University
founded 1931
Cultural Region
Place of Origin
Dimensions26.2 x 42 x 35 cm (10 5/16 x 16 9/16 x 13 3/4 in.)
Material
Bibliography
DescriptionCircular in shape, this chamber made of metal and glass was put in-between the poles of two strong electromagnets. The cylindrical glass section (the plate cover is now cracked) contained the gas pumped in and out of the chamber from the tubes connected to the lower section of the instrument. The glass wall and plate cover are clamped together by a metallic ring, under which were placed soft rubber gaskets. Six wingnuts are used to secure the whole thing in place.
In Collection(s)
Signedunsigned
FunctionA cloud chamber was used to track (visualize) and study charged particles. To this effect, a chamber was filled with a gas (actually a mixture of vapor in equilibrium with liquid) and a non-condensating gas. To make the elementary particles (in this case known as cosmic rays) appear as visible tracks, the mixture described had to be brought into a supersaturated state by forcing the gas to expand. When this happened, condensation started around the ions generated by the passing of high-energy charged particles. The resulting droplets, the visible tracks, were then photographed.
A video explanation and demonstration of a cloud chamber's function and operation by the Fondazione Scienza e Tecnica in Florence is available on Youtube here.
A video explanation and demonstration of a cloud chamber's function and operation by the Fondazione Scienza e Tecnica in Florence is available on Youtube here.
ProvenanceTransferred to CHSI from the Department of Physics, Jefferson Laboratory, Harvard University, February 6, 1998.
Historical AttributesCloud chamber in which Jabez Curry Street and Edward C. Stevenson identified the mass and decay time of the muon from a photograph of its curved track in 1937. It was built in Street's physics lab at Harvard, circa 1934-35.
The cloud chamber was placed on a pole of a large electromagnet. Street had constructed this magnet in the 1930s using a yoke from a generator discarded by the Boston Street Railways.
The work was done in the Cosmic Ray Shed at Harvard. The shed was considered part of the Research Laboratory of Physics, later renamed the Lyman Lab in 1947.
National Institute of Mental Health
Date: circa 1998
Accessories: computer (2004-1-0403b); computer screen with mask (2004-1-0403c); plus a control box; spare Plexiglas touchscreen mask; food pellet distributor
Object number: 2004-1-0403a
Scientific Prototype Manufacturing Corporation
Date: 1960
Accessories: manual: <i>Laboratory Studies in the Analysis of Behavior</i> by Homme and Klaus (1957)
Object number: 2008-1-0003
B. F. Skinner
Date: circa 1950
Accessories: wire screens (4); electric cord; plastic bag containing a piece of wire and metal connections (orange and white wire)
Object number: WJ1233
Lehigh Valley Electronics
Date: 1980-1990
Accessories: two multiwire gray cables; 1 loose black wire; a removable wire mesh tray
Object number: 1998-1-0013
See also/See also
