Etched Metric: Over a period of many years an abandoned table has become covered in a dark patina of microbial growth. It might not look alive but this is another example a complex microbial ecology which I call the Urban Cryptobiotic Crust (UCC). Here a snail, a leviathan on the scale of the UCC, has fed on this ecology, and in revealing the sterile manmade substratum beneath, has highlighted the table’s microbiology and etched a telling metric into the extended surface of the table.