Every measurement in science, every experimental decision, result and information drawn from it has to cope with something that has long been named by the term "error". In fact, errors describe our limitations when it comes to experimental science and science looks back on a long tradition to cope with them. The widely known way to cope…

Discusses the potential use, by students in cell biology and plant physiology, of isolated chloroplasts for determining the Emerson enhancement effect. The experiment designed to measure spectrophotometrically the photoreduction of a dye by illuminating chloroplasts with short- and long-wavelength light is presented. (HM)

Traces the development of college physics laboratories. Discusses the motivating forces that produced these laboratories, sources of experiments and the first and most influential laboratory manual prepared by E. C. Pickering for use at the Massachusetts Institute of Technology. (JN)

Described is a one-week summer chemistry workshop held at Lebanon Valley College, Annville, Pennsylvania, for secondary school students. Experiments and evaluation results of the workshops are provided. (HM)