The next zone, the _umbrosa pellis_ or _ignis niger_, is a narrow dark shell, whence proceed the more dramatic meteorological events. Here, following on the hints of the Wisdom of Solomon (chap. v) and the Book of Job (chap. xxxviii), are situated the diagrammatically portrayed treasuries of lightning and of hail. From here the tempestuous north wind bursts forth. This _ignis niger_ is clearly comparable to the _dry earthy exhalation_ that works of the Peripatetic school regard as given off by the outer fiery zone. The presence of the _ignis niger_ thus suggests some contact on the part of the authoress with the teaching of the _Meteorologica_ of Aristotle.[59] The outermost layer of all is a mass of flames, the _lucidus ignis_. Here are the sun and the three outer planets, and from here the south wind pours its scorching breath (Fig. 2). The movements of the four outer zones around each other, carrying the heavenly bodies with them, are attributed to the winds in each zone. The seasonal variations in the movements of the heavenly bodies, along with the recurring seasons themselves, are also determined by the prevalent winds, which, acting as the motive power upon the various zones, form a celestial parallelogram of forces. In this way is ingeniously explained also why in spring the days lengthen and in autumn they shorten until in either case an equinox is reached (Fig. 2). ‘I looked and behold the east and the south wind with their collaterals, moving the firmament by the power of their breath, caused it to revolve over the earth from east to west; and in the same way the west and north winds and their collaterals, receiving the impulse and projecting their blast, thrust it back again from west to east.... ‘I saw also that as the days began to lengthen, the south wind and his collaterals gradually raised the firmament in the southern zone upwards towards the north, until the days ceased to grow longer. Then when the days began to shorten, the north wind with his collaterals, shrinking from the brightness of the sun, drove the firmament back gradually southward until by reason of the lengthening days the south wind began yet again to raise it up’[60] (Plates VII and VIII).