Elements of plane and spherical trigonometry (1833)
Young, J. R. (John Radford), 1799-1885 · Philadelphia, Carey, Lea & Blanchard · leaf 47
constant length in whatever direc-tion it be draT^Ti, that is, the bounding line ADB is the circumferenceof a circle of which c is the centre. The circle is, obviously, the larger, as it is nearer to the centre C ofthe sphere, or as its perpendicular distance Cc is less, because CD beingconstant,… … ON TKE SPHERE. 43 of the sphere is called a great circle of the sphere, and every other asmall circle. It ]s obvious that the circumference of a great circle may be drawnthrough any two points on the surface of a sphere, because a plane maybe drawn through these two points and through the centre…
