436K views · 10K reactions | In 1845, the Franklin Expedition set sail on a quest to chart the Arctic - and vanished without a trace. 250 years later, a shocking revelation leads to the ships' discovery underneath the ice, and the gruesome fate of the explorers is finally revealed, in this episode of History’s Greatest Mysteries: Solved, a new History digital original series. | HISTORY | Facebook

Evolution of Comptometers 1904-The End (Models A-3D11)

#4-Compound Meters: Conducting Tip with Michelle Willis