 This system challenged the traditional view that harmonics occur at integer frequency ratios and in consequence all music using this tuning produces low frequency beating.In 2002, Harrison's last manuscript, "A true and short, but full Account of the Foundation of Musick, or, as principally therein, of the Existence of the Natural Notes of Melody", was rediscovered in the US Library of Congress.His theories on the mathematics of bell manufacturing (using "Radical Numbers") are yet to be clearly understood.