钟表运转的奥秘
Tick Tock . Tick Tock . The sounds of clocks and timepieces surround me . I’m standing inside the Willard House & Clock Museum in North Grafton, Massachusetts .
Tick Tock . Tick Tock . The sounds of clocks and timepieces surround me . I’m standing inside the Willard House & Clock Museum in North Grafton, Massachusetts .
The human body works like a machine. Over time, its parts wear out or get damaged. For example, disease may weaken the heart or a bone may break. When the body cannot heal itself, a doctor may repair or replace diseased or broken parts to keep the body running smoothly. Sometimes, a living or dead human donor provides a part. Donations of hearts, lungs, kidneys, bone marrow, blood, and other tissues regularly save lives. But getting new parts from other human beings isn’t the only way to accomplish this.
“Invasion, invasion!” A chemical siren blares. We Scouts all sense its urgency. An enemy has breached the gates and launched an attack on our vast world of InMi.
科幻小说:InMi 世界的入侵者 Continue reading »
What would you think if you sailed into a vast area of ocean that glowed in the dark with pale white light? One sea captain, Raphael Semmes, was traveling along the Horn of Africa in 1864 when he encountered this phenomenon. “We suddenly passed from the deep blue water in which we had been sailing, into a patch of water so white that it startled me,” he wrote.
Watching the Earth: How Do Scientists Gather Information About Our Planet? Continue reading »