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This handbook is designed for the physical education teacher who wishes to emphasize or reinforce metric education. The activities described involve applications of physical skills or principles of health with measuring in the metric system or knowledge of metric measure. (JD)

This handbook describes inexpensive or easy to make metric measuring materials for use by teachers of grades K-12. Materials for teaching length, area, volume, and temperature concepts are suggested. In addition, there is a chapter on games and aids and a bibliography which provides further references. The introduction includes some hints on teaching measurement. (MK)

In order to improve the reliability of welds used in satellite construction, a new welding machine has been developed. This welding machine consists of a set of storage batteries to supply current, a bank of transistor switches to regulate the magnitude and duration of the current, and a commercial welding head. The new welder produces: a pulse whose current and duration can be independently controlled to a high degree of accuracy; a pulse whose current remains very close to its predetermined value regardless of changes in resistance in the weld being made; a pulse which is constant from day-to-day and from machine-to-machine. (Author)

This paper is a report on some of the work done during the past year on the experimental evaluation of the relative thermally emissive properties of certain radiative coatings applied to a series of systematically altered surfaces. These surfaces were made up of multiple V-grooves cut in aluminum, the included angle of which was varied from 22-1/2 to 90 to 90 degrees. It is shown that a 20 percent gain in power dissipation for a given temperature was obtained from the use of a multiple-grooved surface radiator coated with white PV-100 over that of an equivalently painted flat surface, and that a 100 percent gain in power dissipation resulted from using a grooved sandblasted surface instead of a flat sandblasted surface. A preferred groove angle is indicated, based on the data presented. The method used in this work is, in essence, the classical experiment for the determination of the Stefan-Boltzmann constant but differing in the use of samples having emissivities less than unity. (Author)