Note 1667 — Chapter IV · STUDIES OF THE FARMER.

On the effects of the rainbow the ancients held a curious opinion, which Lord Bacon thus expounds:—“It hath been observed by the ancients, that where a rainbow seemeth to hang over or to touch, there breathed forth a sweet smell. The cause is, for that this happeneth but in certain matters which have in themselves some sweetness, which the gentle dew of the rainbow doth draw forth, and the like to soft showers, for they also make the ground sweet, but none are so delicate as the dew of the rainbow where it falleth.” Sylva Sylvarum. 832. His Lordship here, as in many other places, adopts the explanation of the Peripatetics while he seems to be himself assigning the cause of the phenomenon. Aristotle (Problem. 12. 3) enters fully into the subject, which appears to have been brought under the notice of philosophers by the shepherds who had observed that when certain thickets had been laid in ashes the passing of a rainbow over the spot caused a sweet odour to exhale from it. The same fact is noticed by Theophrastus, De Caus. Plant. 6. 17. 7. Cf. Plin. Hist. Nat. 12. 52. 21. 18. 2. 60. To many among the older philosophers that comparatively rare phenomenon, the lunar rainbow, was unknown. (Arist. Meteor. iii. 2: νύκτωρ δ᾽ ἀπὸ σελήνης ὡς μὲν οἱ ἀρχαῖοι ᾢοντο οὐκ ἐγίγνετο·) but in the time of Aristotle it had been observed, and the cause of its pearly whiteness investigated. Cf. Meteorol. iii. 4. 5. Senec. Quæst. Nat. i. 2, sqq.