Though central to any pedagogical development of physics, the concept of mass is still not well understood. Properly defining mass has proven to be far more daunting than contemporary textbooks would have us believe. And yet today the origin of mass is one of the most aggressively pursued areas of research in all of physics. Much of the excitement…

Presented are three theories of superconductivity: (1) the London theory; (2) the Bardeen, Cooper, Schrieffer (BCS) theory; and (3) the sudden-polarization theory. (RH)

Outlined is the history of superconductivity and described are the physical and chemical principles upon which it rests. Some possible applications of superconductors are considered. (RH)

Although the concept of heat permeates the subject of chemistry, conceptual and semantic inconsistencies related to this concept are found in classroom situations and in the literature. These conceptual and semantic inconsistencies are examined, exploring other problematic areas associated with the concept (such as notation and entropy flow). (JN)

Examines issues regarding the defensibility and utility of natural selection as a scientific theory, focusing on the process of population change over time. Topics considered include criticisms of Darwinian theory, tautology and the meaning of fitness, the ability of theories to predict and explain, and the sufficiency of natural selection. (DH)

Discussed is the accuracy of three statements commonly used in chemistry books and in teaching chemistry. (HM)

Describes four kinds of movement by a cat with or without angular momentum and tail or tail-less during free falling. Presents many pictures illustrating the movement. Supports the position that the angular momentum of the tail plays an important role in free fall. (YP)

Explains why the isolated sphere models are physically unsound. Describes an improved model for attempting a qualitative explanation of charge concentration. (YP)

Scientific terms and names included in "Cultural Literacy: What Every American Needs to Know" are analyzed and geology related terms are listed. Some items not listed are considered. (RH)

Discusses recent advances in the study of mammalian immunology. Explains the roles of two families of lymphocytes, the B cells and T cells. Also examines evolutionary mechanisms related to the immune system. (ML)

A variety of problems, ranging from vocabulary to pre-existing belief structures, prevent efficient learning among biology students. Several of these problems are discussed, with implications for teaching college level biology addressed. (JN)

Discusses a number of significant persons and ideas in the European development of notions relating to faunal succession. Major focus is on the 17th through the 19th centuries, from the onset of rational investigations of the earth to definition of the stratigraphic zone. (JN)

Summarizes steps involved in a systematic method for balancing redox equations by inspection. (CS)

A diffusional driving force, called the radial force, which is responsible for the increase with time of the scalar separation between a fixed point and a particle undergoing three-dimensional Brownian motion, is derived using Boltzmann's equation. (Author/HM)

Discusses the concept of equilibrium in chemical systems, particularly in relation to predicting the position of equilibrium, predicting spontaneity of a reaction, quantitative applications of the equilibrium constant, heterogeneous equilibrium, determination of the solubility product constant, common-ion effect, and dissolution of precipitates.…