WITH A FEW MORE REFLECTIONS ON ASTROLOGY.
M. Duval, who, if I mistake not, was librarian to the Emperor Francis I., gives us an account of the manner in which, in his childhood, pure instinct gave him the first ideas of astronomy. He was contemplating the moon which, as it declined towards the west, seemed to touch the trees of a wood. He doubted not that he should find it behind the trees, and, on running thither, was astonished to see it at the extremity of the horizon.
The following days his curiosity prompted him to watch the course of this luminary, and he was still more surprised to find that it rose and set at various hours. The different forms which it took from week to week, and its total disappearance for some nights, also contributed to fix his attention. All that a child could do was to observe and to admire, and this was doing much; not one in ten thousand has this curiosity and perseverance.
He studied, as he could, for three years, with no other book than the heavens, no other master than his eyes. He observed that the stars did not change their relative positions; but the brilliancy of the planet Venus having caught his attention, it seemed to him to have a particular course, like that of the moon. He watched it every night; it disappeared for a long time; and at length he saw it become the morning instead of the evening star. The course of the sun, which from month to month, rose and set in different parts of the heavens, did not escape him. He marked the solstices with two staves, without knowing what the solstices were.
It appears to me that some profit might be derived from this example, in teaching astronomy to a child of ten or twelve years of age, and with much greater facility than this extraordinary child, of whom I have spoken, taught himself its first elements.
It is a very attractive spectacle for a mind disposed to the contemplation of nature to see that the different phases of the moon are precisely the same as those of a globe round which a lighted candle is moved, showing here a quarter, here the half of its surface, and becoming invisible when an opaque body is interposed between it and the candle. In this manner it was that Galileo explained the true principles of astronomy before the doge and senators of Venice on St. Mark's tower; he demonstrated everything to the eyes.