davidjamesweir’s avatardavidjamesweir’s Twitter Archive—№ 3,593

    1. I'm grateful to one of my research assistants for pointing me to this very cool short video from Hel_Observatory about the 'aikapussi' (time bag) that used to be dropped to allow accurate determination of the time in Helsinki. youtube.com/watch?v=95FauxQe3UQ
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  1. …in reply to @davidjamesweir
    In Edinburgh to this day, there's a time ball on the Nelson Monument (en.wikipedia.org/wiki/Nelson_Monument,_Edinburgh) on Calton Hill, and a time signal fired from a gun (en.wikipedia.org/wiki/Edinburgh_Castle#One_O'Clock_Gun) at the castle. One can probably measure the speed of sound from this video! 🙌 youtube.com/watch?v=OjWL-EvYLEo
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    1. …in reply to @davidjamesweir
      Given the importance of timekeeping in the 19th century, several Time Gun Maps of Edinburgh were developed. These show isochrones for the delay in hearing the gun at different locations in the city: maps.nls.uk/view/75205243
      oh my god twitter doesn’t include alt text from images in their API
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