E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
Ex Ped’e Her’culem.
From this sample you can judge of the whole. Plutarch says that Pythag’oras ingeniously calculated the height of Hercules by comparing the length of various stadia in Greece. A stadium was 600 feet in length, but Hercules’ stadium at Olympia was much longer. Now, says the philosopher, as the stadium of Olympia is longer than an ordinary stadium, so the foot of Hercules was longer than an ordinary foot; and as the foot bears a certain ratió to the height, so the height of Hercules can be easily ascertained. (Varia Scripta.)
