John Napier (1550-1617) spent over twenty years devising his theory of logarithms. He published his methods in 1614 in Mirifici Logarithmorum Canonis Descriptio (A Description of the Wonderful Law of Logarithms). This is considered his most important work and copies of the book are extremely rare.
In the first pages of Mirifici Logarithmorum, Napier established his technique of devising logarithms based upon a point moving according to two progressions.
On page 10, Napier obtained the logarithms for sines, tangents, and secants of arc length.
The Special Collections staff at the Linderman Library of Lehigh University in Bethlehem, Pennsylvania, is pleased to cooperate with the Mathematical Association of America to exhibit this and other items from the Library’s holdings in “Mathematical Treasures.” In particular, Convergence would like to thank Lois Fischer Black, Curator, Special Collections, and Ilhan Citak, Archives and Special Collections Librarian, for their kind assistance in helping to make this display possible. You may use these images in your classroom; all other uses require permission from the Special Collections staff, Linderman Library, Lehigh University.