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132 goes still farther in idiosyncratic departure and actually turns in the opposite direction. Here, then, Laplace's congruity breaks down, but in its place a little attention will show that a new one has arisen. For Saturn's tilt is 27° and Jupiter's 3°, so that with the major planets there is revealed a systematic righting of the planetary axes from inversion through perpendicularity to directness as one proceeds inward toward the Sun.

Another congruity supposed to exist a century ago was the exemplary agreement of all the satellites to follow in their planetary circuits the pattern set them by their primaries round the Sun. But as man has penetrated farther into space and photographic plates have come to be employed, satellites have been revealed which depart from this orderly arrangement. This is the case with the ninth, the outermost, satellite of Saturn and with the eighth, the outermost, of Jupiter. But, as before, the breaking down of one congruity seems but the establishing of another. It appears that only the most distant satellites are permitted such unconformity of demeanor. For departure from the supposed orthodoxy occurs in both instances where the. distance is most, and does not occur in the case of all the other satellites found since Laplace's day, eleven in number, nearer their planets.

A third congruity formerly believed in has suffered