Letters
By Science News
A better way
The article “Thinning fuel before injection boosts efficiency” (SN: 10/25/08, p. 9) shows that there are many ways to find efficiency when we look. One place I see for improvement is moisture injection in the feed airstream to gasoline engines. Here in the Southwest, where humidity runs at 20 percent, rainy days are associated with an increase in gas mileage because the moisture turns to steam in the engine and improves efficiency. Moisture injection should be less complex to accomplish than adding a strong electric field.
Michael Daly, Gallup, N.M.
Good degradation
The deterioration of plastics described in “Long live plastics” (SN: 11/8/08, p. 34) has a brighter side: All those plastic items in landfills won’t last forever.
Paul Etzler, Cedar City, Utah
Plastic items in landfills may not last forever, but plastics aren’t going away tomorrow either. In landfills, sunlight and oxygen — the two biggest threats to plastics and many other materials — are in short supply. Landfills are more like a tightly sealed storage container than a compost pile, says Wilson Hughes, a waste reduction planner for the City of Tucson, Ariz. Even plastics designed to be biodegradable won’t disappear quickly in a landfill. — Sid Perkins