A homemade device for testing particle scattering is described. Also described are experiments in zero gravity conducted in free fall in the cargo space of an airplane belonging to the National Aeronautics and Space Administration. (JN)

A thermal oscillator is a self-sustained, nonlinear oscillating system. One part of the system vibrates continuously because of the transfer of heat. Four such devices, two new and two demonstrated in the 19th century are described. Although each depends on the periodic redistribution of heat, they are all quite different. (Author/JN)

Tandem electrostatic accelerators produce beams of positive ions which are used to penetrate atomic nuclei in a target, inducing nuclear reactions whose study elucidates varied properties of the nucleus. Uses of the system, which acts like a mass spectrometer, are discussed. These include radiocarbon dating measurements. (JN)

Provides a running commentary on a chemistry instructor's first day in a first course in chemistry. Focuses on the use of fire and chemists' attempts to explain this phenomenon. Provides the ongoing descriptions of the experiments, a summary of the observations, and the key comments made by the instructor. (TW)