Venus is thus Hesperus or Vesper, the evening star, when following the sun as she passes from beyond him in superior conjunction to inferior conjunction where she is nearest to the earth.  As she again leaves him behind in her course from this point to the opposite one of superior conjunction, she appears in her second aspect as Phosphorus or Lucifer, “the sun of morning,” and herald of the day, shining as

                          “The fair star
  That gems the glittering coronet of morn.”

II.

THE PHASES OF VENUS.

But the changes in the aspect of Venus due to her varying positions in her orbit are not confined to those which cause her to oscillate with a pendulum movement eastward and westward from the sun.  The discovery that she undergoes phases exactly like those of the moon, followed that of the existence of Jupiter’s satellites as the second great result achieved by the use of the telescope in the hands of Galileo.  The fact that the planets were intrinsically dark bodies revolving round the sun, and reflecting its light, as he and Copernicus had maintained, thus received a further ocular demonstration.  The Florentine astronomer describes in a letter to a friend how the planet, after emerging from superior conjunction as a morning star, gradually loses her rotundity on the side remote from the luminary, changing first to a half sphere and then to a waning crescent; until, after passing through the stage of absolute extinction when intervening between us and the sun, she re-appears as a morning star, and undergoes the same series of transformations in inverse order.  The revelation was indeed so novel and unexpected, that when the slight deformation of the planet’s shape was first detected by him, he did not venture to announce it in plain terms but veiled it, according to the prevailing fashion of the time, under a Latin anagram.  His celebrated sentence—­

  “Haec immatura a me jam frustra leguntur.”

("Those incomplete observations are as yet read by me in vain.”)

forms, by transposing the letters, the more definite statement,

  “Cynthiae figuras aemulatur Mater Amorum.”

("The mother of the loves imitates the aspects of Diana.”)

that is to say, Venus vies with the phases of the moon.  The discovery was an important one from its bearing on popular superstition ascribing to the planets special influences on human affairs, for since they were thus shown to transmit to us only borrowed light, belief in their beneficent or malefic powers over man’s destinies received a rude shock.

[Illustration:  THE PHASES OP VENUS.]