came and is eminently just and sober.’ I find all these details in the cave of the Witch of Atlas, the most elaborately described of Shelley’s caves, except the two gates, and these have a far-off echo in her summer journeys on her cavern river and in her winter sleep in ‘an inextinguishable well of crimson fire.’ We have for the mixing bowls, and jars of stone full of honey, those delights of the senses, ‘sounds of air’ ‘folded in cells of crystal silences,’ ‘liquors clear and sweet’ ‘in crystal vials,’ and for the bees, visions ‘each in his thin sheath like a chrysalis,’ and for ‘the looms of stone’ and ‘raiment of purple stain’ the Witch’s spinning and embroidering; and the Witch herself is a Naiad, and was born from one of the Atlantides, who lay in ‘a chamber of grey rock’ until she was changed by the sun’s embrace into a cloud. When one turns to Shelley for an explanation of the cave and fountain one finds how close his thought was to Porphyry’s. He looked upon thought as a condition of life in generation and believed that the reality beyond was something other than thought. He wrote in his fragment ‘On Life,’ ‘That the basis of all things cannot be, as the popular philosophy alleges, mind, is sufficiently evident. Mind, as far as we have any experience of its properties, and beyond that experience how vain is argument, cannot create, it can only perceive;’ and in another passage he defines mind as existence. Water is his great symbol of existence, and he continually meditates over its mysterious source. In his prose he tells how ‘thought can with difficulty visit the intricate and winding chambers which it inhabits. It is like a river, whose rapid and perpetual stream flows outward.... The caverns of the mind are obscure and shadowy; or pervaded with a lustre, beautiful and bright indeed, but shining not beyond their portals.’ When the Witch has passed in her boat from the caverned river, that is doubtless her own destiny, she passes along the Nile ‘by Moeris and the Mareotid lakes,’ and sees all human life shadowed upon its waters in shadows that ‘never are erased but tremble ever’; and in many a dark and subterranean street under the Nile—new caverns—and along the bank of the Nile; and as she bends over the unhappy, she compares unhappiness to the ‘strife that stirs the liquid surface of man’s life’; and because she can see the reality of things she is described as journeying ‘in the calm depths’ of ‘the wide lake’ we journey over unpiloted. Alastor calls the river that he follows an image of his mind, and thinks that it will be as hard to say where his thought will be when he is dead as where its waters will be in ocean or cloud in a little while. In _Mont Blanc_, a poem so overladen with descriptions in parentheses that one loses sight of its logic, Shelley compares the flowing through our mind of ‘the universe of things,’ which are, he has explained elsewhere, but thoughts, to the flowing of the Arne