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Focuses on research into how quickly the earth cooled, allowing the formation of oceans and the development of life, after its formation. Long-held belief that the earth was a sea of magma until about 3.8 billion years ago, when a more hospitable environment developed; Discovery of tiny crystals of the mineral zircon, which are providing evidence that the earth cooled much sooner, even as early as 4.4 billion years ago; Thermodynamic calculations showing that earth's crust could have solidified within 10 million years under certain circumstances; Durability of zircon crystals, which is why they may have lasted since the earth originally solidified; Investigation into the zircon crystals and what they are able to tell scientists about the earth.

Discusses how many of the useful properties of iron and steel depend on the crystal structure of the metal. How heating and cooling metal may drastically alter its properties because of the subtle changes in the crystal structure; Demonstration devised by Charles F. Walton of how profoundly common steel changes with heating.

Discusses the process of using spectroscopy techniques for cooling gases below the normal temperature of condensation. Reference to how matter at certain frequencies is absorbed while others are not absorbed at all; Consideration of the process of measuring, analyzing, and interpreting the frequencies present in a molecular stream in order to investigate its physical properties; How analysis is sometimes impossible due to the complexity of the spectrum of a compound; Behavior of molecules at low temperatures which are required for high-resolution spectroscopy; Energy transitions associated with change in the rotational motion of a molecule; Possibility for a single photon to cause changes in more than one kind of energy state.

The article focuses on the passive cooling systems in Iranian architecture. In Iran, they circulate cool air through the building and can keep water cold and ice frozen from the winter until the height of the long, hot summer of the country's arid central and eastern plains. Clustering the building reduces the total exposed surfaced area. The walls of the buildings are constructed of adobe brick so that they have a high heat capacity.

Presents the procedures for making a dye laser. Materials needed for the instrument; Recommended cooling method to maintain the uniform temperature of the dye; Disadvantage of using ordinary plastic tubing in the portion of the dye plumbing; Tips on drilling a hole through the axis of the rod that extends outside the quartz tube.

Provides information on the experimental procedures devised by physicists which are capable of lowering the temperature range accessible for research to within millidegrees of absolute zero. Explanation of the helium-3/helium-4 dilution process; Development of the Pomeranchuk method; Information on nuclear cooling; Principle and operation of the dilution refrigerator.

Presents information on the structure of glasses. Observation on the change from a liquid to crystalline solid in the cooling process; Role of oxygen in glassmaking; Importance of the separation process in glass technology.

The article describes the development of the stirling refrigeration cycle by Robert Stirling in 1816, citing how the method has been reversed in a machine for cooling things to very low temperatures. Refrigeration efficiencies of various processes are compared. It is evident that the Philips-Stirling process has superior efficiencies at extremely low temperatures.

Presents scientific news briefs. Lack of a caffeine synthesis enzyme in a type of Coffea arabico plant in Ethiopia; Death of at least three transplant recipients resulting from rabies contracted from the lungs, kidneys and liver from an Arkansas donor who was bitten by a bat; Increase of an alloy's cooling capacity through the addition of small quantities of iron.

Reports on the research by Keith Schwab of the National Security Agency and his colleagues at the University of Maryland who have come close to catching the transition between classical and quantum physics. Brownian motion and its role in quantum fluctuations; How the researchers vibrated a sliver of gold and silicon nitride 0.01 millimeter long: How they cooled the beam; Calculations which suggest that the bean would have to be cooled to one milikelvin before zero point fluctuations could be seen; Alternative which is making a device for holding superconducting electrons.

Hornets may chill out with a bit of electricity, say a group of biologists and physicists from Tel Aviv University. Infrared images of hornets anesthetized in their nest revealed that the cuticle around body parts such as the abdomen could be up to 3 degrees Celsius cooler than the nest material. But insect physiologist Allen Gibbs of the University of Arizona thinks that evaporative cooling could in fact do the trick and that the measurements may be misleading because of differences in air and nest temperature.

That burning sensation on the thighs may become a thing of the past for laptop computer users. Sandia National Laboratories researcher Michael Rightley has devised a way to pipe computer heat out the side. He developed "smart" heat pipes, made from 60-micron-deep channels etched in copper. The self-contained system relies on methanol in the tiny tubes. Heat from a chip or circuit board turns the liquid to gas, which moves warmth to the laptop edge, away from the lap. Once the gas cools, it condenses and travels back to its start point via capillary action. Rightley expects the method to replace laptop heat sinks, which are chunks of metal, affixed next to the source, that can handle up to 100 watts of heat per square centimeter.

Describes the development of a heat pipe by workers at the Los Alamos, National Laboratory in New Mexico that can transmit power per unit of area faster than that which passes through the surface of the sun. Designers of the heat pipe; Components; Operation of the pipe; Use of heat pipes in space and for cooling an orbiting nuclear reactor and distribute energy to other devices.

The article presents several letters to the editor in response to the articles in the previous issues including "Magnetothermoelectricity," by Raymond Wolfe in the June issue and in the column "50 and 100 Years Ago" discussing about the regeneration of severed sutured nerves on the August issue, are presented.