I have my own reasons for valorizing the British Romantics. However, I think it’s fair to say that of the major Romantics, the poet most obviously involved in doubling (in its literal, concrete sense) is Lord Byron. Byron created a plethora of doubles; however, three stand out to me as both the most famous and the most representative; Childe Harold, Don Juan, and Manfred. Childe Harold is both the easiest and the most difficult to address; within the confines of Childe Harold’s Pilgrimage, no screens seem to be thrown up to separate Harold, and a protagonist, represented by “I,” who seems to be Byron himself. Careful, scrutinizing readings of Childe reveal that the markers separating Byron’s protagonist and himself seem to be non-existent. Of the three, this is Byron’s crudest doubling. But Byron is a major poet, and Childe is a major poem, so the doublings do not only occur between Byron and an assumed protagonist that is not him. This passage is the 33rd stanza in Canto the Third:

Even as a broken Mirror, which the glass
In every fragment multiplies— and makes
A thousand images of one that was
The same— and still the more, the more it breaks;
And thus the heart will do which not forsakes,
Living in shattered guise; and still, and cold,
And bloodless, with its sleepless sorrow aches,
Yet withers on till all without is old,
Showing no visible sign, for such things are untold.

The image of the heart as broken-mirror is deceptively simple, and less romantic than its constituent elements might suggest.