Gaskin, Thomas. **E.2008.15 The geometrical construction of a conic section sub-
ject to five conditions of passing through given points and touching given straight lines, deduced from the properties of involution and anharmonic ratio, with a variety of general properties of curves of the second order. Cambridge Eng.': J. Deighton. 1852. viii, 84 pp. 2 folded plates. Sm. 8°,
-Involution, Math, GD 22. -Ratio, anharmonic. -Conia sections.