Machupicchu

I remember I said I would tell you what we learned about the walls of the Inca's.  When visiting a site in Cusco they showed us stones used in making walls and in the stones there were egg shaped indentions in the top of the rock, in these indentions they said they placed tiney pebles with fine sand.  then placed another stone on top of that stone and when the quake would roll the ground the wall would be able to glide back and forth.  Reminds me of the elaborate things the engineres go through to make our buildings quake proof now.  If this isn't clear I am sorry, should have taken a picture but didn't as we just were going so fast and there was so many people I didn't think to do it. :(
glenna