Describes a simple method for purifying catalase for the study of proteins. Procedures are systematically and diagramatically presented. Also identifies polyacrylamide gel electrophoresis, kinetic studies, and apparent molecular weight determination as possible techniques to be used in studying proteins. (ML)

Presents an experiment which enables weed science students to observe first-hand the process of herbicide leaching in soils. Features of this technique which demonstrate the movement of herbicide within a column of soil are outlined. Diagrams are provided of the apparatus employed in the exercise. (ML)

Described is the construction and utilization of a Dewar assembly for measuring the heat of vaporization of liquid nitrogen. The device is fabricated from a thermos bottle replacement filler. (SL)

Describes experiments that can be carried out by freshmen in general science courses. All experiments are prepared with inexpensive equipment and materials. Quantitative data are analyzed intuitively using graphical representations. (JP)

Discusses the importance of children developing personal associations with animals, and suggests that it is the responsibility of schools to teach students how to properly care for pets. With particular reference to Canadian experiences, criticizes the widespread neglect of pets and misuse of animals in school laboratories and science fairs. (JR)

Describes a laboratory method suitable for senior high school classes for investigating possible mechanisms of catalytic function. The Harcourt-Essen reaction is used to demonstrate a catalytic process that can be investigated quantitatively by standard kinetic methods. (JR)

Suggests that the Friedel-Crafts reaction, used for synthesizing a wide range of aromatic compounds, is an ideal vehicle for extended senior high school project work in chemistry. Provides a theoretical discussion of the reaction, suggests a number of suitable investigations, and outlines the experimental details. (JR)

Analyzes the role of experiments in science teaching, and applies this analysis to the teaching of Millikan's experiment in physics. Critically examines an article written by T. J. Harvey entitled Millikan made easy'' which was previously published in The School Science Review. (JR)

Describes a demonstration experiment designed to estimate the equilibrium constant by comparing the conductivities of acetic and hydrochloric acids. (CC)

Describes a course based on laboratory use of three skills as a way of teaching a general method of problem solving. (DF)