Perhaps the most important part of our celebration of 75 years is Viewpoints, a series of papers that will delineate the current state of the chemical art in terms understandable by students and other nonspecialists. Supported by a grant from The Camille and Henry Dreyfus Foundation, Inc., the Viewpoints series will appear each month. On page 13* the Chair of the Viewpoints Editorial Board, Glenn Seaborg, describes the purpose of the series and summarizes the first three papers to appear in it.

Demos, Demos, Demos

It is always nice to have a new set of demos to excite, motivate, and intrigue students. This issue should be just what the doctor ordered. Bruist, page 53*, provides a simple mechanical analogy that will help students learn why DNA adopts a helical conformation. Color is involved in demos by McKelvy (page 55*), Hambly (page 56*), and Hughes (page 57*). If you are interested in a new twist on flame tests, cleansing "mud" with "blood", or solids that change color as the temperature changes, check out these three papers. Fang (page 58*) shows how to determine percent oxygen in air by a simple experiment, and Koubek (page 60*) provides a new way of looking at the amphoteric behavior of aluminum. On page 61* Cortel describes in detail how an electronic top-loading balance can be used to measure paramagnetism of a variety of inorganic substances.

Thermodynamics

Thermodynamics can predict equilibrium concentrations of substances and therefore has many practical applications. An excellent illustration of its utility is provided by Treptow and Jean beginning on page 43*. Their thorough analysis of thermodynamics (and some kinetics) of reactions occurring in a blast furnace illustrates nicely the usefulness of this subject. Another illustration of the importance of the science of heat and work is Kimbrough's paper on heat capacity, body temperature, and hypothermia (page 48*). Surprisingly, subfreezing temperatures are not required for water to remove enough heat from a human body to cause death. To illustrate heat transfers quantitatively using an overhead projector, Hur, Solomon, and Wetzel (page 51*) show how with a projecting thermometer.

New Approaches to Learning

The beginning of a new year is a great time to reassess how we teach, and there is lots of food for thought this month. Rasp (page 64*) suggests that performance evaluation provides a more accurate ways to find out which students really understand and which need to do more work. Beginning on page 67*, Towns provides many good suggestions for getting students to work together effectively in groups. Herman (page 70* has found that investigating, as opposed to verifying, in laboratory can more effectively engage students actively in the learning process.

Gallet (page 72) quotes a number of studies indicating that traditional laboratory teaching does not enhance understanding or learning and suggests that a problem-based laboratory can be much more effective. Hilosky, Sutman, and Schmuckler have done a detailed study of laboratory teaching practices of 24 instructors in 16 colleges and universities to answer the question, "Is Laboratory-Based Instruction in Beginning College-Level Chemistry Worth the Effort and Expense?" Turn to page 100* to find out what they learned.

Ron Gillespie's commentary on general chemistry textbooks in the May issue has generated a number of responses. Most agree with Gillespie's analysis of the problems of general chemistry textbooks and then suggest additional approaches beyond those advocated in May. The letters and Ron's response begin on page 10*.

The Cover

This month's cover story is the 75th year of publication of your Journal. Our diamond anniversary logo consists of a tetrahedron, representing carbon in diamond, with the Journal's 75-year age on its faces. On page 22* Jerry Bell, Chair of the Board of Publication, reflects on the Journal's first 75 years and calls upon you to support its continued contributions.

One aspect of our 75th year celebration that will appear every month is The More Things Change (see page 2, opposite*), which will select from our first, 25th, and 50th volumes papers and quotations that have special relevance to this our 75th year. Many issues we argue about today have been discussed in the Journal throughout its history.

Note: * designates articles of special interest to high school teachers.