Show Notes for August 1, 2019
13 minutes to the moon BBC podcast 12 episodes CuriousMarc and team's restoration of the Apollo AGC on YouTube 29 videos so far Mount Umunhum The Billeter slide rules "Julius Billeter (1828 - 1914) made 'Rechenwalze' (Computing Rollers) cylindrical slide rules for the financial industry based on Billeter's 1894 patent. US Patent No. 513,172 January 23, 1894. French Patent No. 217,367 Nov. 10, 1891. Most of the designs were marked as "System Billeter"."