 Written in numbered paragraphs as was common practice till the 19th century, "Elements" begins with the definition of mathematics and builds on the fundamental operations of arithmetic and number systems, and gradually moves towards more abstract topics.In 1771, Joseph-Louis Lagrange published an addendum titled "Additions to Euler's Elements of Algebra", which featured a number of important mathematical results.The original German title of the book was "Vollständige Anleitung zur Algebra", which literally translates to "Complete Instruction to Algebra".