The Mathematical Gazette: Volume 1 -

Some Old Text-Books
J. H. Hooker
Published online by Cambridge University Press:

15 September 2017, pp. 29-30
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This product of Queen Anne’s reign consists of five parts: I. Arithmetick, Vulgar and Decimal. II. Algebra or Arithmetick in Species. III. The Elements of Geometry. IV. Conick Sections. V. The Arithmetick of Infinites explained, with its application to Superficial and Solid Geometry. To these is added an Appendix of Practical Gauging, and in the eighth edition is also found the History of Logarithms.

Director Circle of a Conic Inscribed in a Triangle
E. P. Rouse
Published online by Cambridge University Press:

15 September 2017, pp. 12-13
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Let TP, TQ (Fig. i.) be tangents to a conic, C its centre, S, H its foci, 2a and 2b its axes. From S draw a perpendicular to TP and produce it to its image S′; then we know that S′T = ST, angle S′TP = PTS, and S′H = major-axis = 2a. Similarly with a perpendicular drawn from H to TQ and produced to its image H′. Thus the two triangles S′TH and STH′ are equal, and the angles S′TS, HTH′, and therefore the halves of these angles, are equal, that is, “the tangents from T are equally inclined to the focal distances of T.′

The Mathematical Gazette