the nature of modern cities

we are always in the midst of our own humble past, its echoes feature in even the most modern of our cities. i have walked through the ancient modern heart of the English/British/Imperial capital and seen vast cliff faces of human engineering rear up above me. so impressive the aching new possibilities of technology, but still so very very old.
we have acreages of brick, flung up in mile wide expanses down broad or thin avenues. what is brick but burned red clay? primitive villagers on the broad banks of the Thames had these before Romans had ever bothered them. they would recognise these brick piles for what they are.
And what of the great glass structures that thrust phallic fingers to the sky? for glass is nothing but liquified sand, still slowly dribbling its way earthwards. I would like to see all that glass in ten centuries time, grown thin at the top and thick at the bottom, streaked like the stained glass in the hearts of ancient cathedrals.