A new instrument called the tunneling microscope has recently been developed that is capable of generating real-space images of surfaces showing atomic structure. Discusses current capabilities, limitations, and the physics involved in the technique. Includes results from a study of silicon crystal surfaces. (JN)

Describes a simple apparatus used to demonstrate the thermal conductivity of gases. Procedures for completing the demonstration are included. (JN)

Describes the design and use of a projectile motion apparatus to illustrate a variety of projective motion results typically discussed in an introductory course. They include independence of horizontal (constant speed) and vertical (constant acceleration) motions, parabolic path shape, and other types of motion. (JN)

Examines problems resulting from different forms of the periodic table, indicating that New York State schools use a form reflecting the International Union of Pure and Applied Chemistry's 1984 recommendations. Other formats used and reasons for standardization are discussed. (DH)

A simple device that aids in plotting poles to planes on structural equal-area diagrams (pi diagrams) is described. It is used in conjunction with a standard equal area Schmidt net to assist students in understanding principles of plotting pi diagrams and for rapid plotting of large amounts of data. (BC)

Describes a birefringence apparatus that can be assembled for less than $100 and can be used to measure both the dimensions and dipole moments of many macromolecules. Details are given of the construction and manipulation of the apparatus. (JN)

A number of classroom aids are described and sources given. Included are microscopes, films, minicomputers, balances, catalogs, and information bulletins. (RH)

Discusses the designs for an inexpensive table for analytical balances, a safety pipet for reagents, and permanent models for determining absolute configurations. (MLH)

Presents theoretical and experimental observations made with a musical toy called Hummer consisting of a corrugated flexible plastic tube about three-feet long and one-inch diam open at both ends. Included are descriptions of three new instruments: the Water Pipe, the Gas-Pipe Corrugahorn Bugle, and the Gas-Pipe Blues Corrugahorn. (CC)