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Keywords from Image Description:
Opfindelsernes bog fig. Drawing of pith ball electroscope invented by John Canton The ball is shown attracted to an electrically charged object held in the hand Opfindelsernes Bog af Andr Ltken Fig Det elektriske Pendul Opfindelsernes Bog Book of inventions by Andr Ltken Ill Morten Bisgaard PDOld PDold Opfindelsernes Bog III