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THE PLANET VENUS.

The probable tilt of the axis of Venus is, however, so veryuncertain, that it may be well to consider the above paragraphas a geometrical exercise upon the possible effects of a certainaxial inclination in a planet, rather than a statement of what isreally to be considered as the state of things probably existingupon Venus itself.

It is certainly the case that the observations and drawingsof the spots and markings upon the surface of Venus , towhich we have already referred as made by De Vico andothers at Rome , in 1839-42, as well as those of some-observers of more recent date, for the most part agree veryfairly with those of Bianchini in the years 1720 and 1727 ; infact, sufficiently well to give, as we have stated, remarkablyaccordant results for the supposed period of its rotationdeduced from their apparent movements. _ And yet modernastronomers (see, for instance, the opinion of Dr. Vogel, inPart II. of the “ Bothkamp Observations,” published in 1873)feel great doubt as to the period in question. Much more,therefore, may we feel extreme uncertainty as to the inclina-tion of the planet’s axis, with regard to which not only domodern observations give no information, but older observa-tions are very discordant.*

To conclude this lecture we will quote, from p. 71 of Cham-bers’ “ Handbook of Descriptive Astronomy,” a translation ofthe curious anagram in which Galileo announced to Keplerthe detection, by means of his telescope, of the phases of Venus ;a discovery which afforded a most important confirmation ofthe truth of the great Copernican theory of the Solar System ,and which, we think, it may still be interesting to read in theform in which it was originally expressed. Galileo wrote:—

Haec immatuta a me, jam frustra, leguntur.—o. y.”

“ These things not ripe (for disclosure) are read, as yet in vain, by me; ’’or,

“ These things not ripe ; at present (read) in vain (by others) are readby me.”

* For further information upon these and many other points of interestconnected with the planet, we may refer our readers to the new editionof the Rev. T. W. Webb ’s “ Celestial Objects for Common Telescopes.”