In the same book Kepler enlarges again on his views in reference to the basis of astrology as concerned with nativities and the importance of planetary conjunctions.  He gives particulars of his own nativity.  “Jupiter nearest the nonagesimal had passed by four degrees the trine of Saturn; the Sun and Venus in conjunction were moving from the latter towards the former, nearly in sextiles with both:  they were also removing from quadratures with Mars, to which Mercury was closely approaching:  the moon drew near to the trine of the same planet, close to the Bull’s Eye even in latitude.  The 25th degree of Gemini was rising, and the 22nd of Aquarius culminating.  That there was this triple configuration on that day—­namely the sextile of Saturn and the Sun, the sextile of Mars and Jupiter, and the quadrature of Mercury and Mars, is proved by the change of weather; for after a frost of some days, that very day became warmer, there was a thaw and a fall of rain.”  This alleged “proof” is interesting as it relies on the same principle which was held to justify the correction of an uncertain birth-time, by reference to illnesses, etc., met with later.  Kepler however goes on to say, “If I am to speak of the results of my studies, what, I pray, can I find in the sky, even remotely alluding to it?  The learned confess that several not despicable branches of philosophy have been newly extricated or amended or brought to perfection by me:  but here my constellations were, not Mercury from the East in the angle of the seventh, and in quadratures with Mars, but Copernicus, but Tycho Brahe, without whose books of observations everything now set by me in the clearest light must have remained buried in darkness; not Saturn predominating Mercury, but my lords the Emperors Rudolph and Matthias, not Capricorn the house of Saturn but Upper Austria, the house of the Emperor, and the ready and unexampled bounty of his nobles to my petition.  Here is that corner, not the western one of the horoscope, but on the earth whither, by permission of my Imperial master, I have betaken myself from a too uneasy Court; and whence, during these years of my life, which now tends towards its setting, emanate these Harmonics and the other matters on which I am engaged.”

The fifth book contains a great deal of nonsense about the harmony of the spheres; the notes contributed by the several planets are gravely set down, that of Mercury having the greatest resemblance to a melody, though perhaps more reminiscent of a bugle-call.  Yet the book is not all worthless for it includes Kepler’s Third Law, which he had diligently sought for years.  In his own words, “The proportion existing between the periodic times of any two planets is exactly the sesquiplicate proportion of the mean distances of the orbits,” or as generally given, “the squares of the periodic times are proportional to the cubes of the mean distances.”  Kepler was evidently transported with delight and