Page:Lorentz Grav1900.djvu/14

 $\varkappa'+\int\limits_{0}^{t}\ n\ dt$.

Further, let λ, μ, and ν be the direction-cosines of the velocity p with respect to: 1st. the radius vector of the perihelion, 2nd. a direction which is got by giving to that radius vector a rotation of 90°, in the direction of the planet's revolution, 3rd. the normal to the plane of the orbit, drawn towards the side whence the planet is seen to revolve in the same direction as the hands of a watch.

Put $$\omega =\varpi - \theta$$, $$\frac{p}{V}=\delta$$ and $$\frac{na}{V}=\delta'$$ (na is the velocity in a circular orbit of radius a).

Then I find for the variations during one revolution

§ 10. I have worked out the case of the planet Mercury, taking 276° and + 34° for the right ascension and declination of the apex of the Sun's motion. I have got the following results: