Provides explanations for the variations in appearance of spectra taken at different pressures and cell lengths. (CS)

Describes several simple experiments that can be used to observe directly the dispersion curve of plasmon surface polaritons (PSP) on flat metal surfaces. A method is described of observing the increonental change in the wave vector of the PSP due to coatings that differ in thickness by a few nanometers. (Author/CS)

Presents experiments that illustrate some physiologically important aspects of ligand binding to hemoglobin. (CS)

Presented is an activity in which students use a microscope to do a forensic hair comparative study and a medullary classification. Mounting methods, medulla types, hair photographs, and activities are described. (DS)

Describes a technique for the supercooling of water, for use in the science classroom, involving adding common salt to a mixture of ice and water. Several investigations are included for use during (and after) the process of supercooling. (DS)

Seven easy-to-do experiments with plants are outlined to aid in teaching children about plants: their search for water, food, and light; a variety of rooting systems; and the effects of soil temperatures. (JMF)

A test is described in which three psychotropic drugs were evaluated for their effects on pregnant rats. Behavioral changes are given. (SA)

Describes an experiment that emphasizes the discrete nature of the different oxidation states of vanadium by the separation of ammonium metavanadate into all four species by ion exchange chromatography. (CS)

Outlined are simple activities for studying soil, which can be conducted in the schoolyard. Concepts include soil profiles, topsoil, soil sizes, making soil, erosion, slope, and water absorption. (SJL)

Describes experiments intended to produce a better understanding of the holographic method of producing images and optical imaging by other optical systems. Application of holography to teaching physics courses is considered. (Author/SA)

Describes and explains some aspects of the motion of a top, the extreme end of which is made round, spinning on surfaces provided with friction. (Author/GA)

A discussion of Edwin Land's experiments with color images from black-and-white photographs. Information is presented for duplication of these experiments by the amateur photographer. (BB)

An activity is described that is designed to give students a chance to learn about speed by calculating their own running or walking speed and the speed of cars. (MP)

Discusses the determination of the position of the absorption maximum in wide bands as well as the confidence limits for such calculations. A simple method, suited for pocket calculators, for the numerical evaluation of these calculations is presented. (BB)

Discusses advantages of radial diffusion assay in determining presence of enzyme and/or rough approximation of amount of enzyme activities. Procedures are included for the preparation of starch-agar plates, and the application and determination of enzyme. Techniques using plant materials (homogenates, tissues, ungerminated embryos, and seedlings)…