All that _I_ could discover about him, I found accidentally in a pamphlet
on Quackery, published in 1805, at Kingston-upon-Hull. In a note to that
little work, I am informed that _Dr_. Katerfelto _practised_ on the people
of London in the influenza of 1782; that he added to his _nostrum_ the
fascinations of hocus pocus; and that among other philosophical apparatus,
he employed the services of some extraordinary _black cats_, with which he
astonished the ignorant, and confounded the vulgar. But he was not, it
seems, so successful in his practice when out of London: not long before
his death, he was committed by the Mayor of Shrewsbury to the common House
of Correction in that town, as a vagrant and impostor. When or how he died
does not appear.

Cowper, when he mentions the name of Katerfelto, in the _Task_, in
alluding to the advertisements of the London newspapers--and probably
wrote the passage in the year 1782. The _Task_ was published complete in
1785.

Whoever has easy access to the newspapers of 1782 or thereabout (as I, at
this moment have not) will most probably discover some amusing particulars
about this _Doctor_, that may attract your readers, few of whom will be
more gratified than

_Great Russell-st_.

W.C.

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