Described are available electronic laboratory balances. Information was supplied by the manufacturers or importers. (RH)

A variety of materials are described including spectrophotometers, chromatographs, voltmeters, recorders, and simple laboratory equipment. (RH)

Presents three brief articles that consider the recovery of silver from film, field trips as a supplement to science major general chemistry laboratory, and the construction of a low-cost colorimeter. (MLH)

Describes a design for a pendulum that can demonstrate the dependence of period on amplitude. Common laboratory supplies are used for construction, and timing is done with a stopwatch. (MLH)

Described is a simple apparatus to determine acceleration due to gravity. It utilizes direct contact switches in lieu of conventional photocells to time the fall of a ball bearing. Accuracies to better than one part in a thousand were obtained. (SL)

Describes and evaluates a line of modular electronic instruments that are designed for use in physics instruction, including a power supply, function generator, and counter/timer. (MLH)

Describes two experimental apparatus which may be used to demonstrate the skin effect phenomenon. One apparatus shows the decrease of a magnetic field as it penetrates a thickness of metal; the other demonstrates the decrease with depth of current in a wire. (Author/MLH)

Describes an advanced undergraduate laboratory experiment for studying thermionic emission. The cathode of a type 922 photodiode is used as an emitter over a temperature range from room temperature to 80 degrees centigrade; the thermionic emission current varies by a factor of 3000 over this temperature range. (MLH)

Discusses a light scattering instrument designed to measure the size of particles in an air flow in approximately 25 microseconds and at a concentration as high as 10,000 particles/cc. Indicates that the measurement can be made for all particles, independent of their index of refraction. (CC)

Author undertook a study to examine new science instruction, science budgets and expenditures for new materials from 133 instructors of elementary science methods representing 94 teacher-training institutions. Teacher preparation for science instruction was the focus of the article. (Author/RK)