A BASIC computer program was written for an experiment that measures the time of a fall of a ball-bearing dropped through a measured distance. However, the timing subroutine was written in machine language. The reason for using machine language, the machine language program, hardware used, and the experiment are discussed. (JN)

Describes: (1) a microcomputer demonstration of autocatalysis; (2) a safe alternative to ethanol and methanol; (3) a simple condenser for test-tube reactions; (4) a new procedure for studying the magnetic properties of transition metal compounds; (5) plasticization of the polymer PVC; and (6) some thoughts on polybasic acids and their salts. (JN)

For the sake of grade school entrants in particular, nonexperimental science fair projects should be encouraged and accepted for science fairs. Support for this approach is given along with several suggestions for projects. Guidelines for judging nonexperimental projects are also included. (DH)

Determined student opinion of the investigative laboratory by surveying both students who had completed an introductory biology course using this format and another group of more advanced students who had taken other courses since this one. Results show that a majority of students feel the format improved their problem-solving skills. (JN)

Biology teachers at Ithaca College have developed a course in experimental methodology and instrumentation that teaches beginning biology students the need for accuracy and precision in measurement. This course is described. (JN)

Describes: (1) demonstrations that have led to serious injury and should not be repeated; (2) demonstrations that are questionable because of the potential for injury; and (3) worldwide demonstrations that should be done, but done with care. Includes nature of potential/actual hazards, procedures used, and reactions involved. (JN)

Offers a series of hands-on activities for introducing students to concepts of energy transfer and conversion. Describes how simple devices as marbles, ramps, and sliders can be used to gauge the transfer of energy and assist in the development of investigative skills. (ML)

Describes an experiment designed to acquaint students with the theory and applications of anodic stripping voltammetry (ASV) as well as such ASV problems as contamination associated with trace analysis. The experimental procedure, instrumentation, and materials discussed are designed to minimize cost and keep procedures as simple as possible. (JM)

Presents an experiment in thermometric titration used in an analytic chemistry-chemical instrumentation course, consisting of two titrations, one a mixture of calcium and magnesium, the other of calcium, magnesium, and barium ions. Provides equipment and solutions list/specifications, graphs, and discussion of results. (JM)

Proposes a simple experiment based on the procedure of Guggenheim and Smith for the determinatin of the dipole moments of two isomeric compounds in nonpolar solvents. Provides background information, laboratory procedures, sample data, results of least squares analysis and discussion of results. (JM)

Discusses two procedures for the identification of nitrate, the standard test ("Brown Ring" test) and a new procedure using triphenylbenzylphosphonium chloride (TPBPC). Effectiveness of both procedures is compared, with the TPBPC test proving to be more sensitive and accurate. (JM)

Presents a novel approach to identification of unknown alcohols using experimental measurements of boiling point and viscosity which are easily obtained without expensive equipment of instrumentation. Provides instructions for preparing capillary viscometer, listing special hints for obtaining good results. (JM)

Presents a series of experiments built around the bacteria found in the intestinal tract of formalinized rats as a model for discussing microbial ecology. Describes methods of examination of intestinal content, student tasks, and discussion questions; also gives a challenge problem to solve.

Describes a recently discovered and translated work by Archimedes in which he constructed a balance to determine the amount of gold in an alloy of gold and silver. A description of the balance (translated verbatim) as found in Archimedes' work "On Balances" is included. (JN)

Objectives, materials needed, procedures, discussion questions, and follow-up activities are provided for five experiments. They include (1) testing for sugars; (2) comparing sugar to artificial sweeteners; (3) chewing gum scientifically; (4) soap making; and (5) making toothpaste. (JN)