据推测，中国人在9世纪发明了黑色粉末。几百年后，中国创新者在1250年左右发明了一种枪支或火器，用作信号和庆祝装置，并且数百年来一直如此。最古老的枪支是黑龙江手枪，其历史可以追溯到1288年。据估计，意大利约有1268只眼镜是最早发明的眼镜。他们被僧侣和学者使用。它们被固定在眼前或鼻子上。边缘擒纵系统的发明取得了重大进展，这使得欧洲第一个机械钟在1280左右成为可能。边缘擒纵机构是机械时钟中的一种机制，通过允许齿轮系以规则的间隔或刻度推进来控制其速率。考古学家发现的最早记录的风车使用在中国是1219年。早期的风车被用来为谷物磨和水泵提供动力。在十字军东征之后，风车的概念传播到欧洲。最早的欧洲设计，记录在1270年。一般来说，这些工厂有四个叶片安装在中央柱上。它们有一个齿轮和齿圈，它将中心轴的水平运动转化为砂轮或砂轮的垂直运动，然后用于泵送水或磨粒。
新加坡南洋理工大学作业代写：黑色粉末
It is assumed that the Chinese invented black powder in the 9th century. A few hundred years later, Chinese innovators invented a gun or firearm around 1250 as a signal and celebration device, and it has been this for centuries. The oldest gun is the Heilongjiang pistol, which dates back to 1288. It is estimated that about 1268 glasses in Italy were the earliest glasses. They are used by monks and scholars. They are fixed in front of the eyes or on the nose. Significant progress has been made in the invention of the edge escapement, which made it possible for the first mechanical clock in Europe to be around 1280. The edge escapement is a mechanism in mechanical clocks that controls the speed of the gear train by allowing it to advance at regular intervals or scales. The earliest recorded windmills discovered by archaeologists were used in China in 1219. Early windmills were used to power grain mills and pumps. After the Crusades, the concept of windmills spread to Europe. The earliest European design was recorded in 1270. In general, these plants have four blades mounted on a central column. They have a gear and ring gear that converts the horizontal motion of the central shaft into a vertical motion of the grinding wheel or grinding wheel and is then used to pump water or abrasive particles.