This image comes from the 13th edition of the Encyclopædia Britannica or earlier. The copyrights for that book have expired in the United States because the book was first published in the US with the publication occurring before January 1, 1930. As such, this image is in the public domain in the United States.
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The Abacus-This was one of the earliest manual computer in the history of computer evolution. Add RR
חשבונייה, כלי חישוב פשוט, שנמצא בשימוש מאז העת העתיקה.