Hi, Pete. I have 3 suggestions:1.) Find the oldest, grumpiest mason you can find and ask him if something like an acid wash will help, what acid to use, and how to do it.
2.) Contact John Leeke at johnleeke@HistoricHomeWorks.com after checking his web site which is www.HistoricHomeWorks.com. He may have a suggestion.
3.) Liberal amounts of grain alcohol taken internally. This will not help your brick but you will not care any more. (I know this was the answer you were hoping for--LOL)
Good luckHenry in MI
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