Adriaan Vlacq

Adriaan Vlacq (1600 to 1667) was a Dutch book publisher and author of mathematical tables, born in Gouda. In 1628 he published his Arithmetica logarithmica, a table of logarithms from 1 to 100,000 to ten decimal places that completed the earlier tables of Henry Briggs, which covered only the values from 1 to 20,000 and 90,001 to 100,000. The new values were computed by Ezechiel de Decker and Vlacq, who calculated and added 70,000 further values to complete the tables. Later works of his carried a shorter trigonometric table called Canon Sinuum. His logarithm table was later extended by Jurij Vega in 1794 and by Alexander John Thompson in 1952. He settled in London in 1632, moved to Paris ten years later with the onset of the English Civil War, and later lived at The Hague, where he died in 1667. A lunar crater bears his name.