安利一个讲科学史的 UP 主：长河劫 ( https://space.bilibili.com/35868098 )
挑两个视频推荐：
【技术史】晚清电报发展的崎岖历程 https://www.bilibili.com/video/BV1Qu4y1H7TP/
从摩尔斯电码的诞生讲到汉字电码编码，以及其对应的收费规则和与之而来的变化。
【科学史】一米应该有多长 https://www.bilibili.com/video/BV1ik4y177YX/
从度量衡到国际单位的演化过程，从地球普适单位讲到宇宙普适单位。
前几天刷推送的时候发现的，讲东西蛮有意思的，好看不火，希望能给你带来些新的知识。
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