On the title page of Hekatompathia or Passionate Century of Love by Thomas Watson (1582), dedicated to Edward Earl of Oxford, the reader is informed about the architecture of the “century” of one-hundred sonnets: “Divided into two parts: whereof, the first expresseth the Authours sufferance in Love: the latter, his long farewell to Love and all his tyrannie.”
The two parts have eighty and twenty sonnets respectively. Part One comprises Sonnets 1 – 80 and Part Two comprises Sonnets 81 – 100:
1————————-80 81———100
When we get to Sonnet 80 at the end of the first part, we are told that the next verse, Sonnet 81, beginning the second part, is shaped “in the form of a pillar” that quite obviously makes it unique and gives it considerable importance:

Sonnet 81 of Watson's sequence, in the form of a pillar, starting Part Two (81-100); and Shakespeare's Sonnet 107 is also the eighty-first verse of his "century," starting Part Two (107-126)
“All such as are but of indifferent capacity, and have some skill in Arithmetic, by viewing this Sonnet following compiled by rule and number, into the form of a pillar, may soon judge how much art and study the Author hath bestowed in the same.”
While working on The Monument it became apparent that the one hundred and fifty-four verses of SHAKE-SPEARES SONNETS (1609) contain the same architecture. The first step is to remove the epilogue of the Bath sonnets, 153-154; and then separate the main body of one hundred and fifty-two sonnets by means of the two envoys, Sonnets 26 and 126.
The result is a central sequence of a hundred sonnets between two series of twenty-six:
1—–26 27—————————-126 127—–152
It came as a surprise to me, after completing The Monument, to find that Edgar I. Fripp in Shakespeare, Man and Artist of 1938 had already discovered the same hundred-sonnet sequence and even related it to Watson’s earlier sequence:
“Centuries or ‘hundreds’ of literary pieces were in fashion,” Fripp wrote, citing “hundreds” of songs, sonnets, prayers, sermons, hymns, flowers, emblems, medical facts and so on. “The Hekotompathia or Passionate Century of Love by Thomas Watson, otherwise a century of passions, may have served as a model for Shakespeare’s century of sonnets,” he continued, adding, “Shakespeare’s Sonnets 27-126 are a century.”
But Fripp had seen no significance in Watson’s dedication to Oxford, who had helped with the manuscript; nor had he realized that Shakespeare’s century is itself divided into two parts, exactly as Watson’s century is divided, that is, Part One with eighty sonnets and Part Two with twenty:
Thomas Watson: 1———————————-80 81————-100
Shake-speare’s: 27——————————–106 107————126
Sonnet 107 is the eighty-first verse and the “pillar” that begins Part Two.
And of course Sonnet 107 is both unique and important as the so-called “dating sonnet,” viewed by most critics as celebrating the release on April 10, 1603 of Henry Wriothesley Earl of Southampton after being “supposed as forfeit to a confined doom” in the Tower. Sonnet 107 also refers to the death of Queen Elizabeth, the “mortal Moon,” a few weeks earlier on March 24, 1603, when King James VI of Scotland was quickly proclaimed King James I of England – without the civil war around succession that had been both predicted and feared.
As shown in The Monument, the eighty sonnets of Part One begin with Sonnet 27 upon Southampton’s arrest on the night of February 8, 1601 and continue until Sonnet 106 upon his final night in the Tower on April 9, 1603; and the twenty sonnets of Part Two begin with his liberation on April 10, 1603 and continue with one sonnet per day until Sonnet 125 upon the Queen’s funeral on April 28, 1603 followed by Sonnet 126, the envoy of farewell.
So it appears that Watson’s century of 1582 had “served as a model” for Shakespeare’s century even more closely than Edgar Fripp had known. And given that Oxford had been so intimately involved in the Watson sequence, we might logically conclude that he repeated its structure in the Shakespeare sequence.
In other words, if “Shakespeare” was borrowing from Watson, as now seems clear, then the view here is that he was borrowing from himself!