国立アメリカ歴史博物館のインスタグラム(amhistorymuseum) - 6月24日 06時22分

A step toward modern computing, this is a replica model of Charles Babbage's "Difference Engine No. 1." In the 1820s, the British mathematician devised a difference engine to automatically calculate and print accurate #mathematical tables. It wasn't built during his lifetime. See it on July 1 when @silibraries exhibition #SILFantasticWorlds opens in our West Wing. #math #innovation #exploration #instamuseum

[BIHAKUEN]UVシールド(UVShield)

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