Mathematical recreations: or, a collection of many problems extracted out of the ancient and modern philosophers: as, secrets and experiments in arithmetick, geometry, cosmography, horologiography ... &c. ... / Written first in Greek and Latin, lately compil'd in French by Henry van Etten [pseud.], and now in English ... Whereunto is added the description and use of the double horizontal dyal, and the general horological ring: invented and written by William Oughtred.

Licence: Public Domain Mark

Credit: Mathematical recreations: or, a collection of many problems extracted out of the ancient and modern philosophers: as, secrets and experiments in arithmetick, geometry, cosmography, horologiography ... &c. ... / Written first in Greek and Latin, lately compil'd in French by Henry van Etten [pseud.], and now in English ... Whereunto is added the description and use of the double horizontal dyal, and the general horological ring: invented and written by William Oughtred. Source: Wellcome Collection.