Warren Parrish says he sat by Joseph's side as he translated by revelation.
Warren Parrish, Letter to the Editor of the Painesville Republican, February 5, 1838, in "Mormonism," Painesville Republican 2, no. 14–15 (February 15, 1838): [3]
I have set by his [Joseph Smith's] side and penned down the translation of the Egyptian Hieroglyphics as he claimed to receive it by direct inspiration from Heaven.
Refer to other record from 1841 for better image scan.