"just at the time that I dated my creation" in Frankenstein

Question

In Chapter Seven of Mary Shelley's Frankenstein, I saw the following sentence:

I remembered also the nervous fever with which I had been seized just at the time that I dated my creation, and which would give an air of delirium to a tale otherwise so utterly improbable.

Judging by the structure, one might be tempted to analyze the sentence as having two relative clauses modifying the nervous fever:

I remembered also the nervous fever ​ (a) with which I had been seized just at the time that I dated my creation, ​ and ​ (b) which would give an air of delirium to a tale otherwise so utterly improbable.

However, the plot apparently contradicts this analysis. Two paragraphs before the quoted passage, Victor said:

Two years had now nearly elapsed since the night on which he first received life

This specification of his creation as happening approximately two years before took place during the night prior to his return to his father's house. In other words, he dated his creation during the night, when he encountered the monster. It is thus rather likely that the boldfaced prepositional phrase is meant to describe the time of Victor's recalling the fever, and should have been positioned to modify the main clause, not the relative clause.

Note also that his nervous fever didn't strike him until after his friend Henry Clerval had visited him, and that was already some time after he created the monster:

"My dear Victor," cried he, "what, for God's sake, is the matter? Do not laugh in that manner. How ill you are! What is the cause of all this?" "Do not ask me," cried I, putting my hands before my eyes, for I thought I saw the dreaded spectre glide into the room; "he can tell.—Oh, save me! save me!" I imagined that the monster seized me; I struggled furiously, and fell down in a fit. Poor Clerval! what must have been his feelings? A meeting, which he anticipated with such joy, so strangely turned to bitterness. But I was not the witness of his grief; for I was lifeless, and did not recover my senses for a long, long time. This was the commencement of a nervous fever, which confined me for several months. During all that time Henry was my only nurse.

Answer 1

In the last paragraph of chapter 3 (of the 1823 edition), when Frankenstein was on the verge of completing his work, he was “oppressed with a slow fever” making him “nervous to a most painful degree”:

The leaves of that year had withered before my work drew near to a close, and now every day showed me more plainly how well I had succeeded. But my enthusiasm was checked by my anxiety, and I appeared rather like one doomed by slavery to toil in the mines, or any other unwholesome trade than an artist occupied by his favourite employment. Every night I was oppressed by a slow fever, and I became nervous to a most painful degree; the fall of a leaf startled me, and I shunned my fellow creatures as if I had been guilty of a crime. Sometimes I grew alarmed at the wreck I perceived that I had become; the energy of my purpose alone sustained me: my labours would soon end, and I believed that exercise and amusement would then drive away incipient disease; and I promised myself both of these when my creation should be complete.

_{Mary Shelley (1823). Frankenstein: or, the Modern Prometheus, volume I, pp. 94–96. London: G. and W. B. Whittaker.}

In the first paragraph of chapter 4, the creature came to life in the early morning:

It was on a dreary night of November, that I beheld the accomplishment of my toils. With an anxiety that almost amounted to agony, I collected the instruments of life around me, that I might infuse a spark of being into the lifeless thing that lay at my feet. It was already one in the morning; the rain pattered dismally against the panes, and my candle was nearly burnt out, when by the glimmer of the half-extinguished light, I saw the dull yellow eye of the creature open; it breathed hard and a convulsive motion agitated its limbs.

_{Shelley, pp. 97–98.}

Frankenstein fled from the creature, and “wretchedly” passed the remainder of the night “in the courtyard”. Too afraid to return to his apartment, he wandered the streets, where he met Clerval descending from a coach. With Clerval’s moral support he plucked up the courage to brave the ascent, and found the creature was gone. The “nervous fever” which Frankenstein then succumbed to was presumably a continuation or worsening of the “slow fever” from chapter 3.

This seems to adequately explain the paragraph quoted at the head of the question. “Date” means “determine or specify the date or time of an event” (OED), and “the time that I dated my creation” means “the time, that I determined [to be] the date of my creation”, not (as wrongly interpreted in the question) “the time at which I determined the date of my creation”, so Frankenstein means that he was seized by the “nervous fever” on the same day that the creature came to life.

Normally one would use “dated to” if this were the meaning, but Shelley has structured the sentence with a relative clause (“the time that I dated my creation [to]”) and it is common to omit the preposition in a relative clause after “time” (and some other words, such as “manner” and “way”), for example,

the time that the unjust man doth thrive [in] (William Shakespeare, The Winter’s Tale IV.4)