Mathemagician Video

[EdS2]

Thanks for that Steve - last year I was looking everywhere for it, and didn't find it. There are many accounts of child prodigies and mental calculation, but I didn't find one quite so colourful.

This was one source, Mathematical Recreations and Essays, by W. W. Rouse Ball. The first edition is from 1892, the fourth, which is easy to find, is from 1905, but it turned out that I needed the ninth edition, from 1920. The bit I was searching is a chapter on Calculating Prodigies, and there's much of interest there. Here it is, starting on page 248:
https://archive.org/details/mathematical...8/mode/1up