Briefly refers to the history, physiological background, and adaptive implications of two theories concerning the limits of sensory discrimination. An experiment is described, suitable for college and high school students, which investigates the validity of the two theories. (CS)

Describes an apparatus that offers a very lucid demonstration of Poisson statistics as applied to electrical currents, and the manner in which such statistics account for shot noise when applied to macroscopic currents. The experiment described is intended for undergraduate physics students. (HM)

Presents two articles which are part of a series concerned with safety in school science in the United Kingdom. The two articles deal with restricted chemicals and experiments. (HM)

Describes the British Gypsum, a school-industry science project, designed to link the school with local industry. Teaching strategy, some experiments, and evaluation of the project are also included. (HM)

This article focuses on the discussion of teaching chemistry to the handicapped and particular techniques that are useful to the communication process. (SA)

Presents a demonstration of the effect of alkyl free radical stability on the rate of free radical halogenation of hydrocarbons. The arenes toluene, ethylbenzene and comene are photobrominated comparatively, using an overhead projector both to provide a light source for the chemical reaction and to project the results on a screen. (CS)

Describes three activities: determination of the heat of combustion of a commercial breakfast cereal, qualitative analysis of halogens using hexane, and production of transparent soap. (CS)

Describes a science laboratory experiment that can be done at home with the assistance of parents or older siblings. It is offered as an alternative to reading assignments or answering questions for homework. Parental assistance is encouraged. (SA)

Described is a method of studying growing crystals in a classroom utilizing a carrousel projector standing vertically. A saturated salt solution is placed on a slide on the lens of the projector and the heat from the projector causes the water to evaporate and salt to crystalize. (Author/DS)

Presents background information, procedure, and results of an experiment, using easily obtainable chemicals and equipment, illustrating chemical kinetics. The experiment may be done in a letter as one four-hour physical chemistry laboratory period. (JN)

Presents a demonstration of wave behavior, and experiments of (1) the determination of the mechanical equivalent of heat, and (2) a "discovery" investigation based on the maximum-span staircase. (CS)

Some simple undergraduate laboratory experiments are described, which verify the energy-momentum relationship of special relativity. These experiments have been designed either to be used as classroom demonstrations or to be carried out by second-year students. (Author/JN)

Describes an exercise using dandelion floral stems to demonstrate the movement of water through cellular membranes. (CS)

Describes experiments, including the measurement of the magnetic moment of a magnet, using noncalibrated materials. Results of these experiments can be checked using calibrated equipment. (SK)

Presents a chemical instrumentation laboratory experiment that introduces the methodology of the fabrication and evaluation of an ion-selective electrode. (CS)