Mathematical Treasure: Jacob Kobel’s Geometrei

The above image is the title page of a 1535 edition of Geometrei by Jacob Kőbel. Images from a 1608 edition can also be found on Convergence, as well as an explanation of the second graphic on this title page. The woodcut illustrates determining a unit of measure called a “rood” by lining up the feet of 16 men.

Today Kőbel’s Geometrei, with its focus on measurement, is classified as a surveying book rather than a geometry book. The picture below shows measuring the height of a tower with Jacob's staffs.

In the next picture, a mirror (spiegel in German) is shown in a diagram with similar triangles.

The page below contains information about measuring fields and one of the graphics used on the title page.

A complete digital scan of Kőbel’s Geometrei, call number TA544 .K63 1535, can be found in the Linda Hall Library Digital Collections.

Images in this article are courtesy of the Linda Hall Library of Science, Engineering & Technology and used with permission. The Linda Hall Library makes available all existing digital images from its collection that are in the public domain to be used for any purpose under the terms of a Creative Commons License CC by 4.0. The Library’s preferred credit line for all use is: “Courtesy of The Linda Hall Library of Science, Engineering & Technology.”

Index to Mathematical Treasures