The Irish antiquary Joseph Cooper Walker comments on possible imitations of Petrarch in the Amoretti, and opines that the missing books of the Faerie Queene were not lost at sea because they were never written. Walker was one of the scholars who assisted Henry John Todd with his edition of Spenser's works. No source is given for Walker's note, which may have been taken from manuscript, though it may also have been taken from one of Walker's two books on Italian literature.
I cannot think the Sonnets of Spenser, the least happy of his productions. If they do not always afford pleasure, they certainly never offend the ear. In general, they flow sweetly; yet they do not always partake of the nature of blank verse, by the lines running into each other at proper intervals. They are not formed exactly on the Italian model; they seem to have been constructed according to the genius of our language. The rhymes in the two first quartets are alternate. And a couplet uniformly closes every sonnet. His Amoretti do not seem to be the effusions of a genuine passion. They are Platonick flights. They were probably written in emulation of Petrarcha. This particularly appeas from the 83d Sonnet.
Let not one spark of filthy lustful fire
Break out, that may her sacred peace molest;
No one light glance of sensual desire
Attempt to work her gentle minds unrest.
But pure affections bred in spotless brest, &c.
Though we may often trace Petrarcha in these poems, we seldom discover in them a servile imitation of that charming poet; perhaps the closest is the 81st Sonnet.
—when her fair golden hairs
With the loose wind ye waving chance to mark.
Erano i capei d' oro all' aura sparsi.
Petrarc. Sonnet 60.
But, on this occasion, he follows the Tuscan bard no farther. Nor did he probably mean an imitation, when he says,
—her golden tresses
She doth attire under a net of gold.
Tra le chiome dell' or nascose il laccio &c.
Petrarc. Ballata. 6.
It may, perhaps, be however asserted that, though Spenser is not a servile imitator of Petrarcha, he would never have written his Amoretti if he had not read the Sonnets of the Italian bard. In the Amoretti of Spenser there are often "conceits, miserable conceits." They frequently display the beauties, without the faults, of the Italian sonnet.
Where these little pieces were written, does not appear: probably in Ireland. G. W. senior, in his preliminary Sonnet, urges the author to "hie home," and "with his wit illustrate England's fame." If, therefore, Spenser's travels did not extend beyond Ireland, G. W. must allude to his residence in this country, which he calls "forrain land," at the time the Sonnets were written. From the 80th Sonnet, they would seem to have been the relaxation of his muse after "a long race thro' Fairy land." Entangled in the web of allegory, or weary of "so long a race," he probably only wrote a few cantos of the 7th and 8th books, and then suspended the work; which the political distractions, that drove him out of Ireland, prevented him from ever resuming. So that it may be presumed "the deep" is unjustly accused of having "swallowed" what was never written."