What Can We Play With During Spring Festival？

The Spring Festival is a festival of sound and colors. As the spring festival comes， the quiet street becomes lively， there are clatters， firework rings， bright red color， and occasional screams of children from the alleyways. The fireworks are inherited 2000 years ago. They became more interesting since the black powder was founded in Song Dynasty. The sensory stimuli the fireworks brought was more intense and richer. From the soul-stirring double-bang firecracker， to the long firecracker with tremendous power， and the beautiful fireworks display， the Chinese enjoy them as a long tradition.

Black powder is one of the four great inventions in our country. Our ancestors have known clearly of the characteristics of black powder. Firstly， the fireworks big sound could frighten the people， meant that the black powder burnt severely and rapidly. Secondly， the fireworks could be burnt to ashes， meant the makers were able to master the proportions of different components in the black powder without waste.

The main component of traditional firecracker is black powder， the improved firecracker today is mixed in oxidants and perchlorates in the black powder. It is easily burnt up in a closed place. The severity of firecracker is related to the size of particles of the powder. So you cant use coarse particles of black powder in firecrackers， in case the powder is not fully burnt and explodes with no ring. Different firecrackers need different components of exploders， which is why double-bang firecrackers never use refined black powder as their component， in case the powder broke the tube wall and it couldnt rise high into the sky. The exploder of fireworks display is refined potassium perchlorate， magnalium and colour former， which will guarantee the burning speed is fast， the exploding sound is big， the light is bright and the watchers are more excited.

To make sure the watchers will have enough sensory stimuli， big fireworks are always mixed with many illuminants and color formers in themselves. The above two powders are used to strengthen the flash effect and the color effect. The illuminant mainly consists of magnesium and aluminum. In the old times， photographers always lifted a plat with powder on it， the powder was burnt up as flashlight when exploding. The colorful fire work display we can see is due to the color former. The color former made different colors by the color reactions of different metals.