Word: carbonations
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...areas by acquiring such choice firms as John Lobb, the prestigious British shoemaker, and Cristalleries de St. Louis, the 223-year- old French glassware manufacturer. Fancy a pair of calfskin-clad garden shears? (They will set you back $475.) A jungle-print bath towel? ($525.) A suitcase made of carbon fiber, adapted from the sheathing on the European Space Agency's Ariane rocket? ($5,450.) Dumas has expanded the product line to 30,000 items...
...these things alive? That depends on how the term is defined. Surprisingly, there is no clear definition of "life." Most of the criteria put forward in the past are anthropocentric. Life on earth is carbon-based and built around the nucleic acids RNA and DNA, but that may be a historical accident. Most living things metabolize and multiply, but not all. Viruses have no metabolisms of their own; mules cannot reproduce. Many living things grow, but so do clouds and garbage dumps...
...dangerous ultraviolet light to reach the earth's surface. But since Montreal, a consensus had been growing that mere limitation was not enough. All the participating nations agreed that both types of chemicals should be phased out almost entirely by century's end. Moreover, two other destructive chemicals, carbon tetrachloride and methyl chloroform, were added to the protocol, and will be eliminated by 2000 and 2005, respectively...
...scientists assume that the uranium-thorium tests were right and the carbon 14 tests wrong? For one thing, the carbon datings pointed to the strange conclusion that ice ages, thought to be related to changes in the earth's orbit around the sun, have mysteriously lagged behind those changes by a few thousand years. But uranium-thorium dating shows no such lag. Moreover, carbon 14 levels in the air -- and thus the amount ingested by organisms -- are known to vary over time, and that can affect the results of carbon dating...
Uranium-thorium has another advantage besides accuracy: it can be used to date objects up to 500,000 years old, while carbon 14 is good for only a few tens of thousands of years at best. The one drawback of the uranium-thorium technique is that it is useful mostly for marine animals and plants; uranium is more common in seawater than on the surface of the land. Scientists will no doubt continue to use all possible dating methods in the quest to construct an ever more accurate chronology of the earth's history...