1910. Augustus De Morgan was an important innovator in the field of logic. In addition, he made many contributions to the field of mathematics and the chronicling of the history of mathematics. He writes in the Preface that his object has been to notice particularly several points in the principles of algebra and geometry, which have not obtained their due importance in our elementary works on these sciences. Contents: On Arithmetical Notation; Elementary Rules of Arithmetic; Arithmetical Fractions; Decimal Fractions; Algebraical Notation and Principles; Elementary Rules of Algebra; Equations of the First Degree; On the Negative Sign, etc.; Equations of the Second Degree; On Roots in General, and Logarithms; On the Study of Algebra; On the Definitions of Geometry; On Geometrical Reasoning; On Axioms; On Proportion; and Application of Algebra to the Measurement of Lines, Angles, Proportion of Figures and Surfaces. See other titles by this author available from Kessinger Publishing.