XPost: alt.home.repair   
   From: kludge@panix.com   
      
   Gronk   wrote:   
   >Scott Dorsey wrote:   
   >   
   >> Put a small puddle of rainwater on a piece of glass, then let it evaporate   
   >> inside in a clean and dry place.  Does it leave any residue?  Does it leave   
   >> a whole lot of residue?  Does it leave corrosive residue?   
   >   
   >You'd need a lot more than a puddle to see the deposits, although you could   
   >run that experiment with a glass tea kettle to boil the rainwater dry.   
      
   Not around here.  Around here, the rainwater leaves VERY obvious spotting.   
   Layer thick enough that you can see color in it too.   
      
   >As for being corrosive, rain has long stopped being corrosive at the levels   
   >that anyone would notice in their lifetime, even on marble & limestone.   
   >   
   >While pH 5.6 is acidic, it's mostly carbonic acid which is a weak acid.   
      
   Depends where you are.  In Tidewater, VA you can see a big triangle of   
   increased corrosion downwind of the trash-burning plant.   
   --scott   
   --   
   "C'est un Nagra. C'est suisse, et tres, tres precis."   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)