Equátion. n.s. [æquare, Latin.] The investigation of a mean proportion collected from the extremities of excess and defect, to be applied to the whole.
We are to find out the extremities on both sides, and from and between them the middle daily motions of the sun along the Ecliptick; and to frame tables of equation of natural days, to be applied to the mean motion of addition or substraction, as the case shall require. Holder on Time.
By an argument taken from the equations of the times of the eclipses of Jupiter's satellites, it seems that light is propagated in time, spending in its passage from the sun to us about seven minutes of time. Newton's Opt.