The Elements of Euclid : Viz, the First Six Books, Together With the Eleventh and Twelfth : the Errors, by Which Theon, or Others, Have Long Ago Vitiated These Books, Are Corrected, and Some of Euclid's Demonstrations Are Restored : Also, The Book of.

The Elements Of Euclid : Viz, The First Six Books, Together With The Eleventh And Twelfth : The Errors, By Which Theon, Or Others, Have Long Ago Vitiated These Books, Are Corrected, And Some Of Euclid's Demonstrations Are Restored : Also, The Book Of by Euclid. This scholarly edition preserves and extends Euclid's classic treatise with detailed editorial notes, restorations, and corrections aimed at recovering the original demonstration style and mathematical rigor. It surveys Data and its applications across plane and spherical trig, defines angle measures, sine, versed sine, tangent, secant, and co-tangent, and presents Napier-style rules and worked examples for right- and oblique-triangle configurations. The volume situates Euclid's Elements within a broader textual-criticism context, tracing corruptions introduced by editors such as Theon and Campanus and offering restored propositions, prefatory notes, and discussions of parallel planes, figures, and constructions. Additional material surveys the Data section (Definitions I–IX), the editorial apparatus, and appended topics in plane and spherical trigonometry, plus notes on editors and history. Overall, it is a rigorous scholarly resource for advanced geometry and history of mathematics.