Sounds like you need to clean the air.
-jc
On Dec 8, 2004, at 10:58 PM, Met History wrote:
>
> Brick Presbyterian Church, 1939 by York & Sawyer is a muscular red
> brick new england meeting house on 91st and Park Avenue. The
> building was cleaned recently, bringing out the crisp limestone
> carving very nicely. But the slate roof is quite visible for blocks
> around. The slate was not cleaned, is streaked and discolored.
>
> So, has it come to this, Shaman? We need to clean roofs now, too?
>
> christopher