Suggestions for the design, installation, and operation of laboratory fume hoods are listed. (RH)

Describes a micromanipulator that is inexpensive, simple to build, rugged, and capable of several modes of operation beyond those of other types. It can, for example, be used with its controls quite remote from the tool holder and microscope or be controlled by computer. (JN)

The preparation and performance of a graphite (silver/copper sulfide) electrode is described. This rod, extracted from a used dry cell, is an acceptable substitute for ion-selective electrodes after it has been cleaned by abrasion followed by an overnight treatment with hydrochloric acid. (JN)

Presents seven elementary school science experiments designed as good visual demonstrations of basic scientific principles. (JMB)

Describes the construction and use of a nondriven pendulum that can be used in a classroom to demonstrate the rotation of Earth on its axis. (JRH)

Describes the construction of an effective plant incubator for classroom use using a five-gallon plastic bucket. (JRH)

Reviews techniques for online coupling of high-performance liquid chromatography with mass spectrometry, emphasizing those suitable for application to nonvolatile samples. Also summarizes the present status, strengths, and weaknesses of various techniques and discusses potential applications of recently developed techniques for combined liquid…

Describes the construction of a simple, commercial-type electrode which is compact, not orientation sensitive, and requires the minimum of expensive materials (platinum and mercury). (JN)

Microgravity-the absence or reduction of some of the effects of gravity-is an important attribute of free-fall. In microgravity (often incorrectly called zero-g), water no longer flows "downhill" and neither do smoke or steam bubbles rise. This changes a number of chemical and physical activities. Experiments in combustion, fluid behavior,…

Presents a simple experiment to compare the performance of the PASCO Introductory Dynamics System with that of an Ealing student air track. Discusses the relative advantages of both. Concludes that for a wide assortment of motion activities in a low friction environment, or studies of frictional forces, the PASCO Introductory Dynamics System is a…

An easily constructed apparatus that models the effect of penicillin on the structure of bacterial cells is described. Background information and procedures for using the apparatus during a classroom demonstration are included. (JN)

A relatively simple opto-electronic setup is described that utilizes a cadmium sulphide (CdS) photoconductive cell to detect resonance of a stretched vibrating string or wire. The display may be either an oscilloscope or a frequency counter. Also describes an inexpensive socket for flanged-base light bulbs. (JN)

A high-impedance comparator suitable for monitoring the resistivity of a deionized or distilled water line supplying water in the 50 Kohm/cm-2 Mohm/cm range is described. Includes information on required circuits (with diagrams), sensor probe assembly, and calibration techniques. (JN)