Describes experiments on properties of leather performed by a science teacher, assisted by senior science students. Concludes that the finish layer contributes a major part of the resistance to air passage, reducing permeability of leather. Flexing increases permeability and may, in its action, discriminate between finishes. (Author/JN)

Four means of altering fat levels in laboratory mice, contrasting invasive injection techniques with non-invasive dietary and behavioral means, are described. Relates these investigations concerning obesity to the practicality of using animal models as an approach in searching for physiological knowledge about human beings. (CS)