A treatise on spherical trigonometry, and its application to geodesy and astronomy, with numerous examples. By John Casey.

164 Index.
Neuberg, theorems by, 22, 91, 94, 96, 97, 98, 103, 138, 139, 140.
Norm, 22, 31.
Oblique angle, reduction to the horizon, 143, 144.
Obliquity of the ecliptic, 150-155.
Octahedron, 129-131.
Parallelogram, 18.
Parallelopiped, 131-134.
Parts of a triangle, 19.
Pascal's theorem, 111.
Points, double of involution, 158.
homothetic, 103.
inverse, 103, 123.
Poles of a circle on the sphere, 3.
- of the heavens, 149.
- of the primitive, 122.
Poles and polars, 106-111.
Polyhedra, 128-142.
Power, spherical, 100.
mutual, 112-118.
Primitive, 121-127.
Proceedings of the Royal Irish Academy, 116, 158.
Prouhet, proofs by, 43, 89.
Quadrantal triangles, 81, 112.
Ratio of section, 67.
- anharmonic, 68, 69, 70, 158.
Radical circle, 101, 102.
Roy, application of Girard's theorem, 117.
Rule, mnemonic, Napier's, 35.
- of transformation, 32, 85.
Roy's, 148.
Salmon, theorem by generalized, 111.
Serret, applications of stereographie projection, 124-127.
Similitude, axes of, 104.
centres of, 103-106.
Solution, oblique-angled triangles, 54-64.
---- - right-angled triangles, 49-54.
Sphere, elementary properties, 1-8.
Staudt, definition of sine of solid angle, 22.
Staudtians, 22, 23, 132, 140.
Steiner, theorems, 72, 75, 81, 92, 93, 95, 127, 156.
Stereographic projection, 121-128.
Stewart, theorem by, generalised, 24.
Supplemental triangles, 11.
Symmedian lines of a triangle, 159.