Lewis Perin wrote:
>> ... you have to clear the tannins out by adding a little bit of
>> portland cement first... the cement adsorbs the tannins and gives
>> you a cup of clear liquid.
>
> Ugh! I don't mind a touch of ammonia in my cup any more than the next
> guy, but portland cement ... !

One old engineering definition of portland cement is "A hydraulic cement
made by finely pulverizing the clinker produced by calcining to
incipient fusion a mixture of calcareous and argillaceous earths."
How could anyone resist such a confection?