Researchers at the George Mason University are using 30-60 Hz acoustic wave signals to put off fire. This works because what sound is really a longitudinal wave traveling through space. i.e
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This work is quintessential because in places like the ISS fire extinguishers are not as effective as they are on earth because they spread out in all directions.
But sound waves on the other hand can be directed to quench the flame.
Mælifell is a beautifully shaped mountain placed on in the Highland in Iceland. It is in a middle of a large black sand area behind Mýrdalsjökull, the glacier that houses the sleeping and scary volcano Katla.
The altitude of the sand is approximately 600 meters, and Mælifell is about 200 meters, a bit less than 800 meters above sea-line. But despite the fact that the mountain is in the cold highland it is covered with vegetation that makes it unique when standing in the middle of the black sand
The ‘Devil’s Bridge’ is a 19th-century structure in Kromlau, Germany, that was designed to make a perfect circle with its reflection in the water below. Source
One of several places I stayed in Colorado. Built into the canyon cliff, one entire side of the house is rock; the shower and reading corner are natural recesses. Wood-burning stove, heated tile floors, and 2nd story loft for guest bed.
