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CHAP. VIII.
BVt why doth not the Rain-bow,* 1.1 in stead of this great and halfe circle it maketh, become wholly round? Some thinke thus, that the sunne being far more higher then the clouds, beateth not, but vpon the vpper part, whence it followeth that the inferiour i•• not attainted with light. Entertaining the sunne therefore but in one part, they likewise represent but a part of the sunne, and this part is neuer more great then the halfe. This reason hath no great waight•• Why? because tha•• although the sunne incl••neth towards the higher part, yet beateth he vpon the whole cloud. He hath coloured it then: why not? since it is his custome to dart his beames, and to penetrate thorow euery thicknesse. Moreouer, they contra∣dict their owne intent; for if the sunne be aboue, and for this cause reflecteth only on the higher part of the clouds, neuer will the Arke descend vnto the earth; but we see that it extendeth it selfe euen vnto the ground•• Furthermore, the Arch is alwayes opposite against the sun, neither appertaineth it any thing to the matter, whether it be aboue or beneath the same, because that euery place that is opposite against the sunne, cannot but be beaten with the beame•• thereof. Againe, sometimes a Westerly sunne causeth a Rain••bow, when a•• he reflecteth vpon the clouds beneath; and is nearest to the earth, which a•• that time hath but his halfe circle, although the clouds receiue the sunne, when he tendeth to his declination. The Stoickes that would haue th•• light appeare in the cloud, as a fire doth in the mirror, say, that the cloud is hollow, and as it were a halfe bowle, which cannot make an entire globe, because it is onely a part ther∣of. I approue their intention, but not their argument. For if in the cauitie of a mirror, all the face of the opposite orbe is expressed, then in an halfe orbe there is no cause why the whole globe may not be beheld, and if we haue said here∣tofore that a man seeth entire circles of the same colours as the Rain-bow, en∣uironing the Sun and the Moone: whence commeth it in the meane space, that these circles are entirely whole, and the Rain-bow is neuer but halfe a circle? Againe, why do hollow clouds, and such as are not flat and round, receiue and entertaine the sunne? Aristotle saith, That after the AEquinoctiall in Autumne the Rain-bow is made euery houre of the day, but that in Summer it is neuer seene, but vpon sun-rise, or sun-set. The cause is euident. First, because about noonested the sun is so strong that he disperseth the clouds, by meanes where∣of he cannot impresse his image in them. But in the morning and euening he hath least force, and therefore the clouds may sustaine and repulse him. More∣ouer, whereas he is not accustomed to forme the Arch, except at such time as he is opposite to those clouds where he causeth the same; when the dayes are shor∣ter, then is he alwayes oblique. Therefore in euery part of the day, yea euen at mid-day there are certaine clouds, that he may oppositely beate vpon. But in Summer time he is caried aboue our heads, by meanes whereof, at noone-day he beholdeth the earth so directly, that there is not any cloud that can be oppo∣sed against him, for at that time they are all vnder him.