As it is difficult to make any good sense here of 'can' alone, we should perhaps read 'can make', or 'can give,' making 'Genius' a trisyllable, and the line of six feet.
"Or night kept chain'd below.—'Tis fairly spoke."
"Thy banks with pioned and twilled brims."
'Banks' may be either the margins of streams or hillocks, or slight elevations of land; but 'brims,' which can only be the edges or margins of hollows, shows that it is the former that is meant. 'Pioned' seems to be a word of Shakespeare's own creation; for, finding the word pioneer in common use, and pyonings—a word of Spenser's coinage—in the Faerie Queen (ii. 10. 63) signifying defences, the work of pioneers, he thought himself at liberty to form a verb pion. This is generally taken to mean dig; and 'twilled' is supposed to be a term transferred from cloth, etc., and signifying ridged; and so the passage is made to mean dug, and laid out in ridges, which, however, hardly accords with the context. Steevens, on the other hand, read 'pioned and lilied'; but neither the piony nor the lily can properly be regarded as a wild flower (though the former is said to grow on the Severn), and such only could be meant here. Others again for 'twilled' read tilled, or give strange meanings to 'twilled.' My own opinion is, that the sense which Shakespeare gave to his 'pioned' was fenced, and that 'twilled' was a printer's error. We may observe that 'and twilled' is pronounced an twilled, which differs very slightly in sound from 'and willow'd.' (See Introd. p. [52].) By reading, then, "Thy banks with pioned and willow'd brims" we get most excellent sense, the idea in the poet's mind being the bank of a stream, fenced, as it were, and secured against overflow, with a range of willows along its edge, and 'betrimmed,' i.e. adorned, with primroses, violets, and other wild flowers; for "April showers bring forth May flowers." I have not hesitated to make this correction in my Edition.
"To make cold nymphs chaste crowns."
In my Edition I have here transposed the adjectives (See on i. 1). We are to take 'cold,' as so frequently, in the sense of cool, which agrees well with flowers growing on the edge of a stream, while it seems absurd to term them 'chaste.' 'Nymphs' is evidently maidens; for if the Naiades were meant there would be an article.