Ye guardian Gods, on whom the Fates depend Of tottering Albion! Ye eternal fires, 620 That lead thro’ heav’n the wandering year! Ye powers, That o’er th’ incircling elements preside! May nothing worse than what this age has seen Arrive! Enough abroad, enough at home Has Albion bled. Here a distemper’d heaven 625 Has thin’d her cities; from those lofty cliffs That awe proud Gaul, to Thule’s wintry reign; While in the West, beyond th’ Atlantic foam, Her bravest sons, keen for the fight, have died The death of cowards, and of common men; 630 Sunk void of wounds, and fall’n without renown. But from these views the weeping Muses turn, And other themes invite my wandering song. [Illustration] BOOK IV. The PASSIONS. The choice of aliment, the choice of air, The use of toil and all external things, Already sung; it now remains to trace What good what evil from ourselves proceeds: And how the subtle principle within 5 Inspires with health, or mines with strange decay The passive body. Ye poetic Shades, That know the secrets of the world unseen, Assist my song! For, in a doubtful theme Engag’d, I wander thro’ mysterious ways. 10 There is, they say, (and I believe there is) A spark within us of th’ immortal fire, That animates and moulds the grosser frame; And when the body sinks, escapes to heaven, Its native seat; and mixes with the Gods. 15 Mean while this heavenly particle pervades The mortal elements, in every nerve It thrills with pleasure, or grows mad with pain. And, in its secret conclave, as it feels The body’s woes and joys, this ruling power 20 Weilds at its will the dull material world, And is the body’s health or malady. By its own toil the gross corporeal frame Fatigues, extenuates, or destroys itself: Nor less the labours of the mind corrode 25 The solid fabric. For by subtle parts, And viewless atoms, secret Nature moves The mighty wheels of this stupendous world. By subtle fluids pour’d thro’ subtle tubes The natural, vital, functions are perform’d. 30 By these the stubborn aliments are tam’d; The toiling heart distributes life and strength; These the still-crumbling frame rebuild; and these Are lost in thinking, and dissolve in air.