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中国是最早发明火药的国家。隋朝时,有炼丹士就发现将“硝石、硫磺和木炭”按照一定的比例和方法混合成的粉末状物体在受热或撞击后会立即引起爆炸和剧烈燃烧,而单一的“硝石、硫磺、木炭”都不具备这种特性。到了明朝,据《纪效新书》、《武备志》等书籍的记录,硝75.75%、硫10.6%、炭13.6%的比例使得火药的威力更加巨大,而且更加稳定。

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    If you're dreaming of visiting one of those picture-perfect European towns filled with old-world attractiveness and scenic beauty, here is a look at the most beautiful small towns in Europe.

    Manarola

    Manarola, Italy, is filled with rainbow-colored homes carved right into a wall of stone along the Mediterranean coast. This charming fishing town is famous for its unbelievable wine, and the paintings. There are no cars here, no traffic lights, or traffic noise. You can drive to Manarola, but you'll have to park just outside the town and then take a shuttle bus or walk in on foot.

    Garmisch-Partenkirchen

    Garmisch-Partenkirchen, Germany, is a fascinating mountain town. Once two separate towns, one Roman and the other Teutonic, the 1936 Winter Olympics forced them to combine, though the two sides still have different characters. The town dates back to 15 AD, filled with narrow, cobblestoned streets lined with historic three or four-story buildings painted with regional and religious scenes.

    Marsaxlokk

    The energetic trading port of Marsaxlokk, Malta, was built in 900 BC. Today, this pictures-like town is the main supplier of fish to the island nation that sits in the Mediterranean Sea. It has no modern buildings to ruin its appeal. With such quiet surroundings, including the traditional luzzu's (fishing boats), it's a particularly charming place to visit.

    Portmagee, Ireland

    In a country filled with beautiful towns, Portmagee, is a standout, sitting on the southwest coast of Ireland. This postcard-perfect seaside fishing town has a row of brightly colored buildings along with a rich and colorful history. At The Bridge Bar, you'll find live music many nights of the week along with fantastic food and a fine glass of beer.