To construct the parabola when the focus and directrix are given, draw the axis CD and bisect CF at G, which gives the vertex.
Broad, and containing woo lines, and consider the effect of interpolating an additional moo lines, so as to bisect the former intervals.
We must bisect as far as may be, but the division is after all to be into limbs, not parts.
Driver prefers to bisect the dialogue by supposing i.
In measuring differences of declination, where the stars are brought up by the diurnal motion, this precaution cannot be adopted, because it is necessary always to bisect the preceding star with the fixed web.
To test this parallelism the single web must be made to bisect the images of both components simultaneously, as in fig.
The edges are then separated till they are tangent to the opposite limbs of the disk of the planet to be measured, or till they respectively bisect two stars, the angle between which is to be determined.
If the one set of lines exactly bisect the intervals between the others, the grating interval is practically halved, and the previously existing spectra of odd order vanish.
Upon an axis concentric with the declination axis is carried a plane mirror, which is geared so as always to bisect the angle between the polar axis and the optical axis of the telescope.