Simon Newcomb

“ The most remarkable feature of these bodies is that, instead of the planes of their orbits being near that of the ecliptic, they are actually inclined to it nearly 90° The result is that, as the planet performs its orbital revolution, there are two opposite points near which the orbits are seen edgewise, and the satellites seem to us to swing north and south on each side of the planet. ”

“ The positions of the satellites in the orbits at any time may be found from the following elements, where u is the angular distance from the node upon a plane parallel to that of the Earth’s equator, and the motion is that in a Julian year.
The epoch force is 1872, January 0, Washington mean noon. The mean distance is the angle subtended by the radius of the orbit as seen at the mean distance of Uranus from the Sun (log a=1·28310) . ”

“ Indeed, doubts of their reality sometimes found expression until, in 1873, they were observed with the Washington 26-inch telescope, and observations upon them showed their identity with the objects discovered by Lassell. ”