each row to the margin (rows 32, 2 and 1) and this value (35) is the square root required, or at least the integer part of it (the actual value is 35.1852....). Napier provides a second example for calculating the square root of 2209 (= 47). See also Jeton References John Napier; translated by William Frank Richardson; introduction by Robin E. Rider (1990). Rabdology. MIT Press. . Martin Gardner (1986). Knotted doughnuts and other mathematical entertainments. W. H. Freeman and Company. . Specific External links Javascript simulation of Location arithmetic Mathematical tools Arithmetic