Joseph Ady or Adey (c. 1770–1852) was an English impostor.
He was at one time a hatter in London, but failing in that business he hit upon the device of raising funds by means of circular letters, promising, on the receipt of a suitable fee, to inform those whom he addressed of ‘something to their advantage.’[1] In numerous instances he evaded the law and baffled the magistrates and Post Office authorities.[2]
For some months prior to his death in 1852, he was removed from prison to his brother's residence in Fenchurch Street, in consequence of a rapid decline of health, a memorial to that effect having been presented to the home secretary.