Dear List,
While rooting around in the list archives, I happened on a 2006 post from the late, great Stan Kelly-Bootle (we miss you, Stan!) where he checked VN's math from the following passage in SM, and found it correct:
"A foolish tutor had explained logarithms to me much too early, and I had read (in a British publication, the Boy's Own Paper, I believe) about a certain Hindu calculator who in exactly two seconds could find the seventeenth root of, say, 3529471145760275132301897342055866171392 (I am not sure if I have got this right; anyway the root was 212)"
I did a little searching and was able to find VN's probable source, which was not (or likely not) the Boy's Own Paper, but actually a much later publication, the 1931 Proceedings of the Society for Psychical Research. In Google Books I was only able to access the "snippet view," so I don't have the whole passage, but I was able to see the following:
A HINDU ARITHMETICAL GENIUS In the American spiritualistic journal 'Immortality' for June-July 1931 appears a short account ... If the facts are as stated, it may be admitted that he has a claim to be regarded as the greatest mathematical prodigy the world has ever seen. ... He found the 17th root of the number 3529471145760275132301897342055866171392 in one second, giving it as 212.
VN was an enthusiastic reader of the SPR's proceedings, so it's not hard to imagine him writing down this anecdote for later use.
Matt Roth
remembering and dissembling
It's interesting that Nabokov dissembles about remembering the number when it is so exact. He seems to intimate that he memorized it from his youthful reading of a Boy's magazine. That would be quite a feat in itself – is that what he wants us to think? Or did he just remember the root 212 and calculate from there? Yet unless the SPR is relating a historical event from the early 1900's, it seems much more likely that, as an avid reader of the journal, he would have saved that article as an adult.
Not that it really matters, that much – it makes a better story this way and his boyhood scarlet fever/mathematics delirium was clearly a momentous event in his life, recurring several times in his writing. When he uses this trope, it is always accompanied by ambiguous hints of spiritual transcendence, e.g. John Shade's "fits," or the governess' delerium in his short story "Easter Rain."
I think it is actually possible that VN did not have scarlet fever but did have a precocious transcendent experience brought about from calculating enormous sums. I have heard of people (even know one) who have had enlightenment experiences from contemplating infinity – the mind can't contain it and capitulates into the Void. No one expects such things from a child, and diagnoses such as "scarlet fever," "fits", "growing pains" are given instead. I believe VN had this sort of opening and it accounts for his psychic experience of "seeing," when he was recovering, his mother buy him a pencil.
Nabokov always allows two readings of such transcendent events, probably so as not to be labeled a mystic. There is a kind of embarrassment when returning to "everyday" reality after an experience of expansion, especially when it is not to be believed. That is the "shame" that young John Shade felt.